From: Lucas Bajolet <r4pass@hotmail.com>
Date: Tue, 10 Feb 2015 18:18:41 +0000 (-0500)
Subject: lib/standard/stream: Renamed streams for more explicit denomination
X-Git-Tag: v0.7.2~17^2~1
X-Git-Url: http://nitlanguage.org

lib/standard/stream: Renamed streams for more explicit denomination

Signed-off-by: Lucas Bajolet <r4pass@hotmail.com>
---

diff --git a/benchmarks/languages/bench_base.nit b/benchmarks/languages/bench_base.nit
index 69590af..9f79133 100644
--- a/benchmarks/languages/bench_base.nit
+++ b/benchmarks/languages/bench_base.nit
@@ -48,7 +48,7 @@ class Generator
 		middle = (dept + 1) / 2
 	end
 
-	var file: nullable OFStream = null
+	var file: nullable FileWriter = null
 	fun write(str: String)
 	do
 		file.write(str)
@@ -62,7 +62,7 @@ class Generator
 	do
 		dir = "{dir}/nit"
 		dir.mkdir
-		file = new OFStream.open("{dir}/{name}.nit")
+		file = new FileWriter.open("{dir}/{name}.nit")
 
 		write "class Root\n\tfun id: Int do return 0\nend"
 		for c in classes do
@@ -117,7 +117,7 @@ class Generator
 	do
 		dir = "{dir}/java"
 		dir.mkdir
-		file = new OFStream.open("{dir}/{name}.java")
+		file = new FileWriter.open("{dir}/{name}.java")
 
 		var cl = ""
 		if interfaces then cl = "X"
@@ -183,7 +183,7 @@ class Generator
 	do
 		dir = "{dir}/cs"
 		dir.mkdir
-		file = new OFStream.open("{dir}/{name}.cs")
+		file = new FileWriter.open("{dir}/{name}.cs")
 
 		var cl = ""
 		if interfaces then cl = "X"
@@ -248,7 +248,7 @@ class Generator
 	do
 		dir = "{dir}/scala"
 		dir.mkdir
-		file = new OFStream.open("{dir}/{name}.scala")
+		file = new FileWriter.open("{dir}/{name}.scala")
 
 		var cl = ""
 		write "object {name} \{"
@@ -316,7 +316,7 @@ class Generator
 	do
 		dir = "{dir}/cpp"
 		dir.mkdir
-		file = new OFStream.open("{dir}/{name}.cpp")
+		file = new FileWriter.open("{dir}/{name}.cpp")
 
 		write "#include <iostream>"
 		write "#include <stdlib.h>"
@@ -374,7 +374,7 @@ class Generator
 			dir = "{dir}/es/{name}"
 		end
 		dir.mkdir
-		file = new OFStream.open("{dir}/root.e")
+		file = new FileWriter.open("{dir}/root.e")
 
 		var istk = ""
 		if se then istk = " is"
@@ -384,7 +384,7 @@ class Generator
 		file.close
 
 		for c in classes do
-			file = new OFStream.open("{dir}/{c}.e")
+			file = new FileWriter.open("{dir}/{c}.e")
 			write "class {c}[E] "
 			if c.supers.is_empty then
 				write "\tinherit ROOT"
@@ -398,7 +398,7 @@ class Generator
 			file.close
 		end
 
-		file = new OFStream.open("{dir}/app{name}.e")
+		file = new FileWriter.open("{dir}/app{name}.e")
 		write "class APP{name.to_upper}"
 		if se then
 			write "insert ARGUMENTS"
diff --git a/contrib/benitlux/src/benitlux_controller.nit b/contrib/benitlux/src/benitlux_controller.nit
index 84ae549..2297bbd 100644
--- a/contrib/benitlux/src/benitlux_controller.nit
+++ b/contrib/benitlux/src/benitlux_controller.nit
@@ -70,7 +70,7 @@ class BenitluxSubscriptionAction
 		end
 
 		if sample_email_path.file_exists then
-			var f = new IFStream.open(sample_email_path)
+			var f = new FileReader.open(sample_email_path)
 			var lines = new Array[String]
 			for line in f.read_all.split_with("\n") do if not line.is_empty then lines.add line
 			f.close
@@ -108,7 +108,7 @@ class BenitluxRESTAction
 				return response
 			end
 
-			var stream = new StringOStream
+			var stream = new StringWriter
 			var serializer = new JsonSerializer(stream)
 			serializer.serialize events
 			var serialized = stream.to_s
diff --git a/contrib/benitlux/src/benitlux_daily.nit b/contrib/benitlux/src/benitlux_daily.nit
index 64f6e15..35aa64c 100644
--- a/contrib/benitlux/src/benitlux_daily.nit
+++ b/contrib/benitlux/src/benitlux_daily.nit
@@ -112,7 +112,7 @@ class Benitlux
 		generate_email(beer_events)
 
 		# Save as sample email to file
-		var f = new OFStream.open(sample_email_path)
+		var f = new FileWriter.open(sample_email_path)
 		f.write email_title + "\n"
 		for line in email_content do f.write line + "\n"
 		f.close
diff --git a/contrib/brainfuck/brainfuck.nit b/contrib/brainfuck/brainfuck.nit
index c35b08a..f7de908 100644
--- a/contrib/brainfuck/brainfuck.nit
+++ b/contrib/brainfuck/brainfuck.nit
@@ -39,7 +39,7 @@ class BFInterpreter
 
 	# Create an interpreter for the file located at `path`.
 	init from_file(path: String) do
-		var ifs = new IFStream.open(path)
+		var ifs = new FileReader.open(path)
 		init(ifs.read_all)
 	end
 
diff --git a/contrib/inkscape_tools/src/svg_to_png_and_nit.nit b/contrib/inkscape_tools/src/svg_to_png_and_nit.nit
index 2a94089..b24cbf5 100644
--- a/contrib/inkscape_tools/src/svg_to_png_and_nit.nit
+++ b/contrib/inkscape_tools/src/svg_to_png_and_nit.nit
@@ -141,7 +141,7 @@ for drawing in drawings do
 	# Inkscape doesn't give us this information
 	var page_width = -1
 	var page_height = -1
-	var svg_file = new IFStream.open(drawing)
+	var svg_file = new FileReader.open(drawing)
 	while not svg_file.eof do
 		var line = svg_file.read_line
 
@@ -164,7 +164,7 @@ for drawing in drawings do
 
 	# Query Inkscape
 	var prog = "inkscape"
-	var proc = new IProcess.from_a(prog, ["--without-gui", "--query-all", drawing])
+	var proc = new ProcessReader.from_a(prog, ["--without-gui", "--query-all", drawing])
 
 	var min_x = 1000000
 	var min_y = 1000000
@@ -240,7 +240,7 @@ for drawing in drawings do
 	end
 
 	# Output source file
-	var src_file = new OFStream.open("{src_path}/{drawing_name}.nit")
+	var src_file = new FileWriter.open("{src_path}/{drawing_name}.nit")
 	nit_src.write_to(src_file)
 	src_file.close
 
diff --git a/contrib/jwrapper/src/code_generator.nit b/contrib/jwrapper/src/code_generator.nit
index 917074d..f0be48c 100644
--- a/contrib/jwrapper/src/code_generator.nit
+++ b/contrib/jwrapper/src/code_generator.nit
@@ -23,14 +23,14 @@ class CodeGenerator
 
 	var with_attributes: Bool
 	var comment_unknown_types: Bool
-	var file_out: OFStream
+	var file_out: FileWriter
 	var java_class: JavaClass
 	var nb_params: Int
 	var module_name: nullable String = null
 
 	init (file_name: String, jclass: JavaClass, with_attributes, comment: Bool)
 	do
-		file_out = new OFStream.open(file_name)
+		file_out = new FileWriter.open(file_name)
 
 		var nit_ext = ".nit"
 		if file_name.has_suffix(nit_ext) then
diff --git a/contrib/jwrapper/src/jwrapper.nit b/contrib/jwrapper/src/jwrapper.nit
index 56128b7..dd3f8ef 100644
--- a/contrib/jwrapper/src/jwrapper.nit
+++ b/contrib/jwrapper/src/jwrapper.nit
@@ -63,7 +63,7 @@ if not "javap".program_is_in_path then
 	exit 1
 end
 
-var javap = new IProcess("javap", "-public", dot_class)
+var javap = new ProcessReader("javap", "-public", dot_class)
 
 var p = new TestParser_javap
 var tree = p.work(javap.read_all)
diff --git a/contrib/jwrapper/src/model.nit b/contrib/jwrapper/src/model.nit
index cb99a23..34792c9 100644
--- a/contrib/jwrapper/src/model.nit
+++ b/contrib/jwrapper/src/model.nit
@@ -176,7 +176,7 @@ class JavaType
 
 		var regex = "extern class [a-zA-Z1-9]\\\+[ ]\\\+in[ ]\\\+\"Java\"[ ]*`\{[ ]*" + self.to_s + "\\\+[ ]*`\}"
 		var nit_dir = "NIT_DIR".environ
-		var grep = new IProcess("grep", "-r", regex, nit_dir/"lib/android/", nit_dir/"lib/java/")
+		var grep = new ProcessReader("grep", "-r", regex, nit_dir/"lib/android/", nit_dir/"lib/java/")
 		var to_eat = ["private", "extern", "class"]
 
 		var output = grep.read_line
diff --git a/contrib/nitcc/src/autom.nit b/contrib/nitcc/src/autom.nit
index 1367e0d..f286894 100644
--- a/contrib/nitcc/src/autom.nit
+++ b/contrib/nitcc/src/autom.nit
@@ -443,7 +443,7 @@ class Automaton
 			ni += 1
 		end
 
-		var f = new OFStream.open(filepath) 
+		var f = new FileWriter.open(filepath)
                 f.write("digraph g \{\n")
 
 		for s in states do
@@ -638,10 +638,10 @@ private class DFAGenerator
 	var automaton: Automaton
 	var parser: nullable String
 
-	var out: OStream is noinit
+	var out: Writer is noinit
 
 	init do
-		self.out = new OFStream.open(filepath)
+		self.out = new FileWriter.open(filepath)
 	end
 
 	fun add(s: String) do out.write(s)
diff --git a/contrib/nitcc/src/grammar.nit b/contrib/nitcc/src/grammar.nit
index b9ac2f8..e77f4e9 100644
--- a/contrib/nitcc/src/grammar.nit
+++ b/contrib/nitcc/src/grammar.nit
@@ -575,7 +575,7 @@ class LRAutomaton
 	# Generate a graphviz file of the automaton
 	fun to_dot(path: String)
 	do
-		var f = new OFStream.open(path)
+		var f = new FileWriter.open(path)
 		f.write("digraph g \{\n")
 		f.write("rankdir=LR;\n")
 		f.write("node[shape=Mrecord,height=0];\n")
@@ -622,7 +622,7 @@ class LRAutomaton
 	do
 		var gen = new Generator
 		gen.gen_to_nit(self, name)
-		var f = new OFStream.open(filepath)
+		var f = new FileWriter.open(filepath)
 		for s in gen.out do
 			f.write(s)
 			f.write("\n")
diff --git a/contrib/nitcc/src/nitcc.nit b/contrib/nitcc/src/nitcc.nit
index 0cc9d2a..a499217 100644
--- a/contrib/nitcc/src/nitcc.nit
+++ b/contrib/nitcc/src/nitcc.nit
@@ -27,7 +27,7 @@ var fi = args.first
 
 var text
 if fi != "-" then
-	var f = new IFStream.open(fi)
+	var f = new FileReader.open(fi)
 	text = f.read_all
 	f.close
 else
@@ -94,7 +94,7 @@ for prod in gram.prods do nbalts += prod.alts.length
 print "Concrete grammar: {gram.prods.length} productions, {nbalts} alternatives (see {name}.concrete_grammar.out)"
 
 var pretty = gram.pretty
-var f = new OFStream.open("{name}.concrete_grammar.out")
+var f = new FileWriter.open("{name}.concrete_grammar.out")
 f.write "// Concrete grammar of {name}\n"
 f.write pretty
 f.close
@@ -102,7 +102,7 @@ f.close
 print "LR automaton: {lr.states.length} states (see {name}.lr.dot and {name}.lr.out)"
 lr.to_dot("{name}.lr.dot")
 pretty = lr.pretty
-f = new OFStream.open("{name}.lr.out")
+f = new FileWriter.open("{name}.lr.out")
 f.write "// LR automaton of {name}\n"
 f.write pretty
 f.close
@@ -142,7 +142,7 @@ print "Generate {name}_lexer.nit {name}_parser.nit {name}_test_parser.nit"
 dfa.gen_to_nit("{name}_lexer.nit", name, "{name}_parser")
 lr.gen_to_nit("{name}_parser.nit", name)
 
-f = new OFStream.open("{name}_test_parser.nit")
+f = new FileWriter.open("{name}_test_parser.nit")
 f.write """# Generated by nitcc for the language {{{name}}}
 
 # Standalone parser tester for the language {{{name}}}
diff --git a/contrib/nitcc/src/nitcc_parser_gen.nit b/contrib/nitcc/src/nitcc_parser_gen.nit
index 65608d0..c15238b 100644
--- a/contrib/nitcc/src/nitcc_parser_gen.nit
+++ b/contrib/nitcc/src/nitcc_parser_gen.nit
@@ -198,6 +198,6 @@ a.to_dot("nitcc0.lr.dot")
 
 a.gen_to_nit("nitcc_parser.nit", "nitcc")
 
-var f = new OFStream.open("nitcc_lexer.nit")
+var f = new FileWriter.open("nitcc_lexer.nit")
 f.write("import nitcc_lexer0\n")
 f.close
diff --git a/contrib/nitester/src/nitester.nit b/contrib/nitester/src/nitester.nit
index eed0d4b..11df5b2 100644
--- a/contrib/nitester/src/nitester.nit
+++ b/contrib/nitester/src/nitester.nit
@@ -180,7 +180,7 @@ abstract class Processor
 		var skip_path = "tests/turing.skip"
 		var skip
 		if skip_path.file_exists then
-			var skip_file = new IFStream.open(skip_path)
+			var skip_file = new FileReader.open(skip_path)
 			skip = skip_file.read_lines
 			skip_file.close
 		else
@@ -463,7 +463,7 @@ class Worker
 					sys.system cmd
 
 					# Test results were written to file, read them
-					var fstream = new IFStream.open(tests_sh_out)
+					var fstream = new FileReader.open(tests_sh_out)
 					var content = fstream.read_all
 					fstream.close
 
diff --git a/contrib/nitiwiki/src/wiki_base.nit b/contrib/nitiwiki/src/wiki_base.nit
index 3dec44f..fa78818 100644
--- a/contrib/nitiwiki/src/wiki_base.nit
+++ b/contrib/nitiwiki/src/wiki_base.nit
@@ -113,7 +113,7 @@ class Nitiwiki
 	# List markdown source files from a directory.
 	fun list_md_files(dir: String): Array[String] do
 		var files = new Array[String]
-		var pipe = new IProcess("find", dir, "-name", "*.md")
+		var pipe = new ProcessReader("find", dir, "-name", "*.md")
 		while not pipe.eof do
 			var file = pipe.read_line
 			if file == "" then break # last line
@@ -512,7 +512,7 @@ class WikiArticle
 	# Page content.
 	#
 	# What you want to be displayed in the page.
-	var content: nullable Streamable = null
+	var content: nullable Writable = null
 
 	# Headlines ids and titles.
 	var headlines = new ArrayMap[String, HeadLine]
@@ -540,7 +540,7 @@ class WikiArticle
 	# REQUIRE: `has_source`.
 	fun md: String is cached do
 		assert has_source
-		var file = new IFStream.open(src_full_path.to_s)
+		var file = new FileReader.open(src_full_path.to_s)
 		var md = file.read_all
 		file.close
 		return md
diff --git a/contrib/nitiwiki/src/wiki_html.nit b/contrib/nitiwiki/src/wiki_html.nit
index 89546ce..10ab09b 100644
--- a/contrib/nitiwiki/src/wiki_html.nit
+++ b/contrib/nitiwiki/src/wiki_html.nit
@@ -52,7 +52,7 @@ redef class WikiEntry
 	fun url: String do return wiki.config.root_url.join_path(breadcrumbs.join("/"))
 
 	# Get a `<a>` template link to `self`
-	fun tpl_link: Streamable do
+	fun tpl_link: Writable do
 		return "<a href=\"{url}\">{title}</a>"
 	end
 end
@@ -215,7 +215,7 @@ redef class WikiArticle
 	end
 
 	# Generate the HTML header for this article.
-	fun tpl_header: Streamable do
+	fun tpl_header: Writable do
 		var file = header_file
 		if not wiki.has_template(file) then return ""
 		return wiki.load_template(file)
@@ -237,7 +237,7 @@ redef class WikiArticle
 	# Generate the HTML summary for this article.
 	#
 	# Based on `headlines`
-	fun tpl_summary: Streamable do
+	fun tpl_summary: Writable do
 		var headlines = self.headlines
 		var tpl = new Template
 		tpl.add "<ul class=\"summary list-unstyled\">"
@@ -265,7 +265,7 @@ redef class WikiArticle
 	end
 
 	# Generate the HTML menu for this article.
-	fun tpl_menu: Streamable do
+	fun tpl_menu: Writable do
 		var file = menu_file
 		if not wiki.has_template(file) then return ""
 		var tpl = wiki.load_template(file)
@@ -288,7 +288,7 @@ redef class WikiArticle
 	end
 
 	# Generate the HTML footer for this article.
-	fun tpl_footer: Streamable do
+	fun tpl_footer: Writable do
 		var file = footer_file
 		if not wiki.has_template(file) then return ""
 		var tpl = wiki.load_template(file)
@@ -342,10 +342,10 @@ class TplArticle
 	super Template
 
 	# Article title.
-	var title: nullable Streamable = null
+	var title: nullable Writable = null
 
 	# Article HTML body.
-	var body: nullable Streamable = null
+	var body: nullable Writable = null
 
 	# Sidebar of this article (if any).
 	var sidebar: nullable TplSidebar = null
@@ -354,7 +354,7 @@ class TplArticle
 	var breadcrumbs: nullable TplBreadcrumbs = null
 
 	# Init `self` with a `title`.
-	init with_title(title: Streamable) do
+	init with_title(title: Writable) do
 		self.title = title
 	end
 
@@ -389,7 +389,7 @@ class TplSidebar
 	super Template
 
 	# Blocks are `Stremable` pieces that will be rendered in the sidebar.
-	var blocks = new Array[Streamable]
+	var blocks = new Array[Writable]
 
 	redef fun rendering do
 		for block in blocks do
diff --git a/contrib/online_ide/sources/nit/pnacl_nit.nit b/contrib/online_ide/sources/nit/pnacl_nit.nit
index 7d0e701..74c7be0 100644
--- a/contrib/online_ide/sources/nit/pnacl_nit.nit
+++ b/contrib/online_ide/sources/nit/pnacl_nit.nit
@@ -63,8 +63,8 @@ redef class ToolContext
 	end
 end
 
-# We have to redef some IFStream methods because we don't use NativeFiles anymore.
-redef class IFStream
+# We have to redef some FileReader methods because we don't use NativeFiles anymore.
+redef class FileReader
 
 	# Looks in the 'files' HashMap.
 	redef init open(path: String)
diff --git a/contrib/opportunity/src/templates/boilerplate.nit b/contrib/opportunity/src/templates/boilerplate.nit
index 609f56c..a92ab4b 100644
--- a/contrib/opportunity/src/templates/boilerplate.nit
+++ b/contrib/opportunity/src/templates/boilerplate.nit
@@ -111,7 +111,7 @@ class OpportunityPage
 	var header = new OpportunityHeader
 
 	# The HTML code of the body.
-	var body: Streamable = "" is writable
+	var body: Writable = "" is writable
 
 	# The HTML code of the footer.
 	var footer = new OpportunityFooter
diff --git a/contrib/opportunity/src/templates/meetup.nit b/contrib/opportunity/src/templates/meetup.nit
index e5d1f56..6eca566 100644
--- a/contrib/opportunity/src/templates/meetup.nit
+++ b/contrib/opportunity/src/templates/meetup.nit
@@ -266,7 +266,7 @@ end
 
 redef class Meetup
 	# Build the HTML for `self`
-	fun to_html(db: OpportunityDB): Streamable do
+	fun to_html(db: OpportunityDB): Writable do
 		var t = new Template
 		t.add """
 <div class="container">
diff --git a/contrib/pep8analysis/src/ast/ast_base.nit b/contrib/pep8analysis/src/ast/ast_base.nit
index 6759fcc..562873a 100644
--- a/contrib/pep8analysis/src/ast/ast_base.nit
+++ b/contrib/pep8analysis/src/ast/ast_base.nit
@@ -4,11 +4,11 @@ import parser
 redef class AnalysisManager
 	fun build_ast_from_file( filename : String ) : nullable AListing
 	do
-		var file = new IFStream.open( filename )
+		var file = new FileReader.open( filename )
 		return build_ast(filename, file)
 	end
 
-	fun build_ast(filename: String, stream: IStream): nullable AListing
+	fun build_ast(filename: String, stream: Reader): nullable AListing
 	do
 		var source = new SourceFile(filename, stream)
 		var lexer = new Lexer(source)
diff --git a/contrib/pep8analysis/src/cfg/dot_printer.nit b/contrib/pep8analysis/src/cfg/dot_printer.nit
index 8fec16b..0bf39c0 100644
--- a/contrib/pep8analysis/src/cfg/dot_printer.nit
+++ b/contrib/pep8analysis/src/cfg/dot_printer.nit
@@ -1,7 +1,7 @@
 import cfg_base
 
 redef class CFG
-	fun print_dot( f: OStream, long: Bool )
+	fun print_dot( f: Writer, long: Bool )
 	do
 		f.write("digraph \{\n")
 		f.write("charset=latin1\n")
@@ -13,7 +13,7 @@ redef class CFG
 end
 
 redef class BasicBlock
-	fun print_dot_nodes( f: OStream, long: Bool )
+	fun print_dot_nodes( f: Writer, long: Bool )
 	do
 		var lbl = "\"{name}:\\n{dot_node_text(long)}\""
 		f.write( "{name} [label={lbl}]\n" )
@@ -36,7 +36,7 @@ redef class BasicBlock
 	fun dot_node_header: String do return ""
 	fun dot_node_footer: String do return ""
 
-	fun print_dot_edges( f: OStream, long: Bool )
+	fun print_dot_edges( f: Writer, long: Bool )
 	do
 		for s in successors do
 			f.write( "{name} -> {s.name}\n" )
diff --git a/contrib/pep8analysis/src/location.nit b/contrib/pep8analysis/src/location.nit
index def0b2e..6fd9edf 100644
--- a/contrib/pep8analysis/src/location.nit
+++ b/contrib/pep8analysis/src/location.nit
@@ -26,7 +26,7 @@ class SourceFile
 	var string: String
 
 	# Create a new sourcefile using a filename and a stream
-	init(filename: String, stream: IStream)
+	init(filename: String, stream: Reader)
 	do
 		self.filename = filename
 		string = stream.read_all
diff --git a/contrib/pep8analysis/src/pep8analysis.nit b/contrib/pep8analysis/src/pep8analysis.nit
index a3231bb..abacc8b 100644
--- a/contrib/pep8analysis/src/pep8analysis.nit
+++ b/contrib/pep8analysis/src/pep8analysis.nit
@@ -57,7 +57,7 @@ redef class AnalysisManager
 			if opt_ast.value then
 				var printer = new ASTPrinter
 				printer.enter_visit(ast)
-				var of = new OFStream.open("{dir}/{mangled_filename.replace(".pep", ".ast.dot")}")
+				var of = new FileWriter.open("{dir}/{mangled_filename.replace(".pep", ".ast.dot")}")
 				of.write printer.str
 				of.close
 			end
@@ -76,7 +76,7 @@ redef class AnalysisManager
 			var cfg = build_cfg(model)
 
 			if opt_cfg.value or opt_cfg_long.value then
-				var of = new OFStream.open("{dir}/{mangled_filename.replace(".pep", ".cfg.dot")}")
+				var of = new FileWriter.open("{dir}/{mangled_filename.replace(".pep", ".cfg.dot")}")
 				cfg.print_dot(of, opt_cfg_long.value)
 				of.close
 			end
@@ -95,7 +95,7 @@ redef class AnalysisManager
 			do_types_analysis(ast, cfg)
 
 			# Print results
-			var of = new OFStream.open("{dir}/{mangled_filename.replace(".pep",".analysis.dot")}")
+			var of = new FileWriter.open("{dir}/{mangled_filename.replace(".pep",".analysis.dot")}")
 			cfg.print_dot(of, true)
 			of.close
 		end
diff --git a/contrib/pep8analysis/src/pep8analysis_web.nit b/contrib/pep8analysis/src/pep8analysis_web.nit
index b991952..4d9d0aa 100644
--- a/contrib/pep8analysis/src/pep8analysis_web.nit
+++ b/contrib/pep8analysis/src/pep8analysis_web.nit
@@ -50,7 +50,7 @@ redef class AnalysisManager
 	do
 		sys.suggest_garbage_collection
 
-		var stream = new StringIStream(src)
+		var stream = new StringReader(src)
 		var ast = build_ast("web", stream)
 		if ast == null then return
 
@@ -95,7 +95,7 @@ redef class AnalysisManager
 		print_notes
 		if notes.is_empty then print "Success: Nothing wrong detected"
 
-		var of = new StringOStream
+		var of = new StringWriter
 		cfg.print_dot(of, false)
 		of.close
 		show_graph(of.to_s)
diff --git a/lib/android/bundle/bundle.nit b/lib/android/bundle/bundle.nit
index 68713ad..3678cbc 100644
--- a/lib/android/bundle/bundle.nit
+++ b/lib/android/bundle/bundle.nit
@@ -672,7 +672,7 @@ redef class Serializable
 	protected fun add_to_bundle(bundle: NativeBundle, key: JavaString)
 	do
 		sys.jni_env.push_local_frame(1)
-		var serialized_string = new StringOStream
+		var serialized_string = new StringWriter
 		var serializer = new JsonSerializer(serialized_string)
 		serializer.serialize(self)
 
@@ -740,7 +740,7 @@ redef class Array[E]
 			var java_string_array = new Array[JavaString]
 
 			for element in self do
-			var serialized_string = new StringOStream
+			var serialized_string = new StringWriter
 				var serializer = new JsonSerializer(serialized_string)
 				serializer.serialize(element)
 				java_string_array.add(serialized_string.to_s.to_java_string)
diff --git a/lib/android/intent/intent_api10.nit b/lib/android/intent/intent_api10.nit
index 005b475..8d84981 100644
--- a/lib/android/intent/intent_api10.nit
+++ b/lib/android/intent/intent_api10.nit
@@ -1285,7 +1285,7 @@ class Intent
 	# Returns `self` allowing fluent programming
 	fun []=(name: String, value: nullable Serializable): Intent
 	do
-		var serialized_string = new StringOStream
+		var serialized_string = new StringWriter
 		var serializer = new JsonSerializer(serialized_string)
 		serializer.serialize(value)
 
diff --git a/lib/android/shared_preferences/shared_preferences_api10.nit b/lib/android/shared_preferences/shared_preferences_api10.nit
index 94aac59..05dbf82 100644
--- a/lib/android/shared_preferences/shared_preferences_api10.nit
+++ b/lib/android/shared_preferences/shared_preferences_api10.nit
@@ -379,7 +379,7 @@ class SharedPreferences
 	# Store `value` as a serialized Json string
 	fun []=(key: String, value: nullable Serializable)
 	do
-		var serialized_string = new StringOStream
+		var serialized_string = new StringWriter
 		var serializer = new JsonSerializer(serialized_string)
 		serializer.serialize(value)
 
diff --git a/lib/csv/csv.nit b/lib/csv/csv.nit
index 441f95c..c6f0b41 100644
--- a/lib/csv/csv.nit
+++ b/lib/csv/csv.nit
@@ -53,7 +53,7 @@ end
 
 # A CSV document representation.
 class CsvDocument
-	super Streamable
+	super Writable
 
 	# The format to use.
 	#
@@ -103,7 +103,7 @@ class CsvDocument
 	# * `has_header`: Is the first row the header?
 	# * `skip_empty`: Do we skip the empty lines?
 	# For details, see `CsvReader.skip_empty`.
-	fun load_from(stream: IStream, has_header: Bool, skip_empty: Bool) do
+	fun load_from(stream: Reader, has_header: Bool, skip_empty: Bool) do
 		var reader = new CsvReader.with_format(stream, format)
 		reader.skip_empty = skip_empty
 		if has_header then
@@ -125,7 +125,7 @@ class CsvDocument
 	# * `has_header`: Is the first row the header?
 	# * `skip_empty`: Do we skip the empty lines?
 	fun load(path: String, has_header: Bool, skip_empty: Bool) do
-		var istream = new IFStream.open(path)
+		var istream = new FileReader.open(path)
 		load_from(istream, has_header, skip_empty)
 		istream.close
 	end
@@ -141,7 +141,7 @@ end
 # delimiters by some parsers.
 #
 # ~~~nit
-# var out = new StringOStream
+# var out = new StringWriter
 # var writer = new CsvWriter(out)
 # writer.write_row(1, 2.0, "foo\nbar")
 # writer.write_sequence([""])
@@ -150,7 +150,7 @@ end
 class CsvWriter
 
 	# The output stream.
-	var ostream: OStream
+	var ostream: Writer
 
 	# The format to use.
 	#
@@ -168,7 +168,7 @@ class CsvWriter
 	var always_escape = false is writable
 
 	# Create a new writer with the specified format.
-	init with_format(ostream:OStream, format: CsvFormat) do
+	init with_format(ostream:Writer, format: CsvFormat) do
 		self.ostream = ostream
 		self.format = format
 	end
@@ -213,7 +213,7 @@ end
 # By default, uses the format recommended by RFC 4180 (see `rfc4180`).
 #
 # ~~~nit
-# var example = new StringIStream("""
+# var example = new StringReader("""
 # foo,bar\r
 # "Hello, word!",1234.5 + 42\r
 # "Something\r
@@ -233,7 +233,7 @@ class CsvReader
 	super Iterator[Array[String]]
 
 	# The input stream.
-	var istream: IStream
+	var istream: Reader
 
 	# The format to use.
 	#
@@ -259,7 +259,7 @@ class CsvReader
 	private var started = false
 
 	# Create a new reader with the specified format.
-	init with_format(istream:IStream, format: CsvFormat) do
+	init with_format(istream:Reader, format: CsvFormat) do
 		self.istream = istream
 		self.format = format
 	end
diff --git a/lib/csv/test_csv.nit b/lib/csv/test_csv.nit
index 68ba4ef..d23d007 100644
--- a/lib/csv/test_csv.nit
+++ b/lib/csv/test_csv.nit
@@ -31,7 +31,7 @@ class TestCsvWriter
 	private fun expect(always_escape: Bool, row: SequenceRead[String],
 			expected_rfc4180: String,
 			expected_custom: String) do
-		var out = new StringOStream
+		var out = new StringWriter
 		var writer = new CsvWriter(out)
 
 		writer.always_escape = always_escape
@@ -43,7 +43,7 @@ class TestCsvWriter
 		end
 		writer.close
 
-		out = new StringOStream
+		out = new StringWriter
 		writer = new CsvWriter.with_format(out, custom_format)
 		writer.always_escape = always_escape
 		writer.write_sequence(row)
@@ -103,15 +103,15 @@ class TestCsvReader
 			input_rfc4180: String,
 			input_custom: String,
 			expected: SequenceRead[SequenceRead[String]]) do
-		var istream: IStream
+		var istream: Reader
 		var reader: CsvReader
 
-		istream = new StringIStream(input_rfc4180)
+		istream = new StringReader(input_rfc4180)
 		reader = new CsvReader(istream)
 		reader.skip_empty = skip_empty
 		assert_table_equals("RFC 4180", reader, expected.iterator)
 
-		istream = new StringIStream(input_custom)
+		istream = new StringReader(input_custom)
 		reader = new CsvReader.with_format(istream, custom_format)
 		reader.skip_empty = skip_empty
 		assert_table_equals("{custom_format.delimiter} " +
diff --git a/lib/filter_stream.nit b/lib/filter_stream.nit
index 8fb57fd..c5baa32 100644
--- a/lib/filter_stream.nit
+++ b/lib/filter_stream.nit
@@ -11,10 +11,10 @@
 # You  are  allowed  to  redistribute it and sell it, alone or is a part of
 # another product.
 
-class FilterIStream
-	super IStream
+class FilterReader
+	super Reader
 	# Filter readed elements
-	var stream: nullable IStream = null
+	var stream: nullable Reader = null
 
 	redef fun eof: Bool
 	do
@@ -23,10 +23,10 @@ class FilterIStream
 	end
 end
 
-class FilterOStream
-	super OStream
+class FilterWriter
+	super Writer
 	# Filter outputed elements
-	var stream: nullable OStream = null
+	var stream: nullable Writer = null
 
 	# Can the stream be used to write
 	redef fun is_writable: Bool
@@ -37,8 +37,8 @@ class FilterOStream
 end
 
 class StreamCat
-	super FilterIStream
-	private var streams: Iterator[IStream]
+	super FilterReader
+	private var streams: Iterator[Reader]
 
 	redef fun eof: Bool
 	do
@@ -53,7 +53,7 @@ class StreamCat
 		end
 	end
 
-	redef fun stream: nullable IStream
+	redef fun stream: nullable Reader
 	do
 		var res = super
 		if res == null and _streams.is_ok then
@@ -79,19 +79,19 @@ class StreamCat
 		end
 	end
 
-	init with_streams(streams: Array[IStream])
+	init with_streams(streams: Array[Reader])
 	do
 		_streams = streams.iterator
 	end
 
-	init(streams: IStream ...) is old_style_init do
+	init(streams: Reader ...) is old_style_init do
 		_streams = streams.iterator
 	end
 end
 
 class StreamDemux
-	super FilterOStream
-	private var streams: Array[OStream]
+	super FilterWriter
+	private var streams: Array[Writer]
 
 	redef fun is_writable: Bool
 	do
@@ -128,12 +128,12 @@ class StreamDemux
 		end
 	end
 
-	init with_streams(streams: Array[OStream])
+	init with_streams(streams: Array[Writer])
 	do
 		_streams = streams
 	end
 
-	init(streams: OStream ...) is old_style_init do
+	init(streams: Writer ...) is old_style_init do
 		_streams = streams
 	end
 end
diff --git a/lib/for_abuse.nit b/lib/for_abuse.nit
index eeb8ed7..812fb02 100644
--- a/lib/for_abuse.nit
+++ b/lib/for_abuse.nit
@@ -38,21 +38,21 @@ end
 
 # Abuser to read a file, see `file_open`
 private class ReadFileForAbuser
-	super ForAbuser[IFStream]
+	super ForAbuser[FileReader]
 	var path: String
 	redef fun iterator do return new ReadFileForAbuserIterator(path)
 end
 
 # Abuser iterator to read a file, see `file_open`
 private class ReadFileForAbuserIterator
-	super Iterator[IFStream]
+	super Iterator[FileReader]
 	var path: String
-	redef var item: IFStream is noinit
+	redef var item: FileReader is noinit
 	redef var is_ok = true
 	init
 	do
 		# start of service is to open the file, and return in
-		item = new IFStream.open(path)
+		item = new FileReader.open(path)
 	end
 	redef fun next
 	do
@@ -159,7 +159,7 @@ end
 #         print l
 #         assert not l.is_empty
 #     end # f is automatically closed here
-fun file_open(path: String): ForAbuser[IFStream]
+fun file_open(path: String): ForAbuser[FileReader]
 do
 	return new ReadFileForAbuser(path)
 end
diff --git a/lib/github/github_curl.nit b/lib/github/github_curl.nit
index 5f6339f..cc12923 100644
--- a/lib/github/github_curl.nit
+++ b/lib/github/github_curl.nit
@@ -136,7 +136,7 @@ end
 # return "" if no such a key
 fun get_github_oauth: String
 do
-	var p = new IProcess("git", "config", "--get", "github.oauthtoken")
+	var p = new ProcessReader("git", "config", "--get", "github.oauthtoken")
 	var token = p.read_line
 	p.wait
 	p.close
diff --git a/lib/html/html.nit b/lib/html/html.nit
index 8d2de2b..b0d6f65 100644
--- a/lib/html/html.nit
+++ b/lib/html/html.nit
@@ -27,7 +27,7 @@ module html
 # HTMLPage use fluent interface so you can chain calls as:
 #	add("div").attr("id", "mydiv").text("My Div")
 class HTMLPage
-	super Streamable
+	super Writable
 
 	# Define head content
 	fun head do end
@@ -86,7 +86,7 @@ end
 
 # An HTML element.
 class HTMLTag
-	super Streamable
+	super Writable
 
 	# HTML element type.
 	#
diff --git a/lib/ini.nit b/lib/ini.nit
index 71868b6..241d22c 100644
--- a/lib/ini.nit
+++ b/lib/ini.nit
@@ -32,7 +32,7 @@ module ini
 #    assert config.has_key("foo.bar")
 #    assert config["foo.bar"] == "foobar"
 class ConfigTree
-	super Streamable
+	super Writable
 
 	# The ini file used to read/store data
 	var ini_file: String
@@ -186,7 +186,7 @@ class ConfigTree
 	#     assert config["goo.boo.baz.bar"] == "gooboobazbar"
 	fun load do
 		roots.clear
-		var stream = new IFStream.open(ini_file)
+		var stream = new FileReader.open(ini_file)
 		var path: nullable String = null
 		while not stream.eof do
 			var line = stream.read_line
diff --git a/lib/io/push_back_reader.nit b/lib/io/push_back_reader.nit
index 5453901..2fa2d19 100644
--- a/lib/io/push_back_reader.nit
+++ b/lib/io/push_back_reader.nit
@@ -13,7 +13,7 @@ module io::push_back_reader
 
 # Input stream that permits to push bytes back to the stream.
 class PushBackReader
-	super IStream
+	super Reader
 
 	# Push the specified byte back to the stream.
 	#
@@ -35,7 +35,7 @@ class PushBackDecorator
 	super PushBackReader
 
 	# The parent stream.
-	var parent: IStream
+	var parent: Reader
 
 	# The stack of the pushed-back bytes.
 	#
diff --git a/lib/io/test_push_back_reader.nit b/lib/io/test_push_back_reader.nit
index bf394aa..1498ccf 100644
--- a/lib/io/test_push_back_reader.nit
+++ b/lib/io/test_push_back_reader.nit
@@ -18,7 +18,7 @@ class TestPushBackDecorator
 	super TestSuite
 
 	private fun sample: PushBackDecorator do
-		return new PushBackDecorator(new StringIStream("""
+		return new PushBackDecorator(new StringReader("""
 abcd
 
 efg
@@ -32,7 +32,7 @@ efg
 	end
 
 	fun test_read_char_eof do
-		var subject = new PushBackDecorator(new StringIStream(""))
+		var subject = new PushBackDecorator(new StringReader(""))
 
 		assert -1 == subject.read_char
 	end
@@ -120,7 +120,7 @@ efg
 	end
 
 	fun test_eof_empty do
-		var subject = new PushBackDecorator(new StringIStream(""))
+		var subject = new PushBackDecorator(new StringReader(""))
 
 		assert subject.eof
 	end
diff --git a/lib/json/store.nit b/lib/json/store.nit
index 8ea6e84..42a04df 100644
--- a/lib/json/store.nit
+++ b/lib/json/store.nit
@@ -130,7 +130,7 @@ class JsonStore
 	private fun store_json(key: String, json: Jsonable) do
 		var path = store_dir / "{key}.json"
 		path.dirname.mkdir
-		var file = new OFStream.open(path)
+		var file = new FileWriter.open(path)
 		file.write(json.to_json)
 		file.close
 	end
@@ -151,7 +151,7 @@ class JsonStore
 	private fun load_json(key: String): nullable Jsonable do
 		assert has_key(key)
 		var path = store_dir / "{key}.json"
-		var file = new IFStream.open(path)
+		var file = new FileReader.open(path)
 		var text = file.read_all
 		file.close
 		return text.parse_json
diff --git a/lib/json_serialization.nit b/lib/json_serialization.nit
index c41426d..4c552f6 100644
--- a/lib/json_serialization.nit
+++ b/lib/json_serialization.nit
@@ -25,7 +25,7 @@ class JsonSerializer
 	super Serializer
 
 	# Target writing stream
-	var stream: OStream
+	var stream: Writer
 
 	redef fun serialize(object)
 	do
diff --git a/lib/libevent.nit b/lib/libevent.nit
index 9ff7ed0..ff9a9f5 100644
--- a/lib/libevent.nit
+++ b/lib/libevent.nit
@@ -165,7 +165,7 @@ class Connection
 	do
 		assert path.file_exists
 
-		var file = new IFStream.open(path)
+		var file = new FileReader.open(path)
 		var output = native_buffer_event.output_buffer
 		var fd = file.fd
 		var length = file.file_stat.size
diff --git a/lib/linux/linux_data_store.nit b/lib/linux/linux_data_store.nit
index 30a6b40..4393f4a 100644
--- a/lib/linux/linux_data_store.nit
+++ b/lib/linux/linux_data_store.nit
@@ -95,7 +95,7 @@ private class LinuxStore
 		if db == null then return
 
 		# Serialize
-		var stream = new StringOStream
+		var stream = new StringWriter
 		var serializer = new JsonSerializer(stream)
 		serializer.serialize value
 		var serialized = stream.to_s
diff --git a/lib/markdown/markdown.nit b/lib/markdown/markdown.nit
index 3c19b0b..10dbcc6 100644
--- a/lib/markdown/markdown.nit
+++ b/lib/markdown/markdown.nit
@@ -118,7 +118,7 @@ class MarkdownProcessor
 	init do self.emitter = new MarkdownEmitter(self)
 
 	# Process the mardown `input` string and return the processed output.
-	fun process(input: String): Streamable do
+	fun process(input: String): Writable do
 		# init processor
 		link_refs.clear
 		last_link_ref = null
@@ -537,7 +537,7 @@ class MarkdownEmitter
 	end
 
 	# Append `e` to current buffer.
-	fun add(e: Streamable) do
+	fun add(e: Writable) do
 		if e isa Text then
 			current_buffer.append e
 		else
@@ -2442,7 +2442,7 @@ redef class String
 	#    var md = "**Hello World!**"
 	#    var html = md.md_to_html
 	#    assert html == "<p><strong>Hello World!</strong></p>\n"
-	fun md_to_html: Streamable do
+	fun md_to_html: Writable do
 		var processor = new MarkdownProcessor
 		return processor.process(self)
 	end
diff --git a/lib/markdown/nitmd.nit b/lib/markdown/nitmd.nit
index 781a484..3570513 100644
--- a/lib/markdown/nitmd.nit
+++ b/lib/markdown/nitmd.nit
@@ -28,7 +28,7 @@ if not file.file_exists then
 	exit 0
 end
 
-var ifs = new IFStream.open(file)
+var ifs = new FileReader.open(file)
 var md = ifs.read_all
 ifs.close
 
diff --git a/lib/mnit/mnit_injected_input.nit b/lib/mnit/mnit_injected_input.nit
index 9d8a819..4d6ddfa 100644
--- a/lib/mnit/mnit_injected_input.nit
+++ b/lib/mnit/mnit_injected_input.nit
@@ -71,7 +71,7 @@ end
 
 redef class App
 	# The stream where injected inputs are read
-	private var injected_input_stream: nullable IStream = null
+	private var injected_input_stream: nullable Reader = null
 
 	redef fun setup
 	do
@@ -84,7 +84,7 @@ redef class App
 
 		var input = "MNIT_READ_INPUT".environ
 		if input != "" then
-			injected_input_stream = new IFStream.open(input)
+			injected_input_stream = new FileReader.open(input)
 			print "GET injected_input_stream {input}"
 		end
 
diff --git a/lib/mnit_linux/linux_assets.nit b/lib/mnit_linux/linux_assets.nit
index 2c75bb5..6749d30 100644
--- a/lib/mnit_linux/linux_assets.nit
+++ b/lib/mnit_linux/linux_assets.nit
@@ -41,7 +41,7 @@ redef class App
 			if ext == "png" or ext == "jpg" or ext == "jpeg" then
 				return new Opengles1Image.from_file( path )
 			else # load as text
-				var f = new IFStream.open(path)
+				var f = new FileReader.open(path)
 				var content = f.read_all
 				f.close
 
diff --git a/lib/mpi.nit b/lib/mpi.nit
index de91686..5696d32 100644
--- a/lib/mpi.nit
+++ b/lib/mpi.nit
@@ -85,7 +85,7 @@ class MPI
 	fun send(data: nullable Serializable, dest: Rank, tag: Tag, comm: Comm)
 	do
 		# Serialize data
-		var stream = new StringOStream
+		var stream = new StringWriter
 		var serializer = new JsonSerializer(stream)
 		serializer.serialize(data)
 
diff --git a/lib/neo4j/graph/json_graph_store.nit b/lib/neo4j/graph/json_graph_store.nit
index 9c97216..fb5ffd0 100644
--- a/lib/neo4j/graph/json_graph_store.nit
+++ b/lib/neo4j/graph/json_graph_store.nit
@@ -44,7 +44,7 @@ import graph
 # b.labels.add "Bar"
 # graph.edges.add new NeoEdge(a, "BAZ", b)
 #
-# var ostream = new StringOStream
+# var ostream = new StringWriter
 # var store = new JsonGraphStore(graph)
 # store.ostream = ostream
 # store.save
@@ -57,7 +57,7 @@ import graph
 #
 # graph.nodes.clear
 # graph.edges.clear
-# store.istream = new StringIStream(ostream.to_s)
+# store.istream = new StringReader(ostream.to_s)
 # store.load
 # assert 1 == graph.edges.length
 # for edge in graph.edges do
@@ -73,13 +73,13 @@ class JsonGraphStore
 	super GraphStore
 
 	# The stream to use for `load`.
-	var istream: nullable IStream = null is writable
+	var istream: nullable Reader = null is writable
 
 	# The stream to use for `save` and `save_part`.
-	var ostream: nullable OStream = null is writable
+	var ostream: nullable Writer = null is writable
 
-	# Use the specified `IOStream`.
-	init from_io(graph: NeoGraph, iostream: IOStream) do
+	# Use the specified `Duplex`.
+	init from_io(graph: NeoGraph, iostream: Duplex) do
 		init(graph)
 		istream = iostream
 		ostream = iostream
@@ -88,14 +88,14 @@ class JsonGraphStore
 	# Use the specified string to load the graph.
 	init from_string(graph: NeoGraph, string: String) do
 		init(graph)
-		istream = new StringIStream(string)
+		istream = new StringReader(string)
 	end
 
 	redef fun isolated_save do return true
 
 	redef fun load do
 		var istream = self.istream
-		assert istream isa IStream
+		assert istream isa Reader
 		fire_started
 		graph.load_json(istream.read_all)
 		fire_done
@@ -103,7 +103,7 @@ class JsonGraphStore
 
 	redef fun save_part(nodes, edges) do
 		var ostream = self.ostream
-		assert ostream isa OStream
+		assert ostream isa Writer
 		fire_started
 		ostream.write(graph.to_json)
 		fire_done
diff --git a/lib/nitcc_runtime.nit b/lib/nitcc_runtime.nit
index 31c0a45..923ef18 100644
--- a/lib/nitcc_runtime.nit
+++ b/lib/nitcc_runtime.nit
@@ -274,7 +274,7 @@ end
 # Print a node (using to_s) on a line and recustively each children indented (with two spaces)
 class TreePrinterVisitor
 	super Visitor
-	var writer: OStream
+	var writer: Writer
 	private var indent = 0
 	redef fun visit(n)
 	do
@@ -322,7 +322,7 @@ abstract class Node
 	# Produce a graphiz file for the syntaxtic tree rooted at `self`.
 	fun to_dot(filepath: String)
 	do
-		var f = new OFStream.open(filepath)
+		var f = new FileWriter.open(filepath)
 		f.write("digraph g \{\n")
 		f.write("rankdir=BT;\n")
 
@@ -346,7 +346,7 @@ abstract class Node
 		f.close
 	end
 
-	private fun to_dot_visitor(f: OStream, a: Array[NToken])
+	private fun to_dot_visitor(f: Writer, a: Array[NToken])
 	do
 		f.write("n{object_id} [label=\"{node_name}\"];\n")
 		for x in children do
@@ -558,7 +558,7 @@ abstract class TestParser
 			end
 			text = args.shift
 		else
-			var f = new IFStream.open(filepath)
+			var f = new FileReader.open(filepath)
 			text = f.read_all
 			f.close
 		end
@@ -582,7 +582,7 @@ abstract class TestParser
 		var tokout = "{name}.tokens.out"
 		print "TOKEN: {tokens.length} tokens (see {tokout})"
 
-		var f = new OFStream.open(tokout)
+		var f = new FileWriter.open(tokout)
 		for t in tokens do
 			f.write "{t.to_s}\n"
 		end
@@ -594,7 +594,7 @@ abstract class TestParser
 		var n = p.parse
 
 		var astout = "{name}.ast.out"
-		f = new OFStream.open(astout)
+		f = new FileWriter.open(astout)
 		var tpv = new TreePrinterVisitor(f)
 		var astdotout = "{name}.ast.dot"
 		if n isa NError then
diff --git a/lib/nitcorn/file_server.nit b/lib/nitcorn/file_server.nit
index 3552b2d..d46d2a4 100644
--- a/lib/nitcorn/file_server.nit
+++ b/lib/nitcorn/file_server.nit
@@ -60,10 +60,10 @@ class FileServer
 	end
 
 	# Error page template for a given `code`
-	fun error_page(code: Int): Streamable do return new ErrorTemplate(code)
+	fun error_page(code: Int): Writable do return new ErrorTemplate(code)
 
 	# Header of each directory page
-	var header: nullable Streamable = null is writable
+	var header: nullable Writable = null is writable
 
 	redef fun answer(request, turi)
 	do
@@ -145,7 +145,7 @@ class FileServer
 					response.header["Content-Type"] = media_types["html"].as(not null)
 				else
 					# It's a single file
-					var file = new IFStream.open(local_file)
+					var file = new FileReader.open(local_file)
 					response.body = file.read_all
 
 					var ext = local_file.file_extension
diff --git a/lib/nitcorn/http_errors.nit b/lib/nitcorn/http_errors.nit
index dd50e0b..1065194 100644
--- a/lib/nitcorn/http_errors.nit
+++ b/lib/nitcorn/http_errors.nit
@@ -29,10 +29,10 @@ class ErrorTemplate
 	var code: Int is writable
 
 	# Header on this page
-	var header: nullable Streamable = null is writable
+	var header: nullable Writable = null is writable
 
 	# Body to show with this page
-	var body: nullable Streamable = null is writable
+	var body: nullable Writable = null is writable
 
 	redef fun rendering
 	do
diff --git a/lib/niti_runtime.nit b/lib/niti_runtime.nit
index a618fba..dd6241b 100644
--- a/lib/niti_runtime.nit
+++ b/lib/niti_runtime.nit
@@ -45,7 +45,7 @@ redef class Sys
 	do
 		if args.is_empty then exit(0)
 		stdin.close
-		stdin = new IFStream.open(args.shift)
+		stdin = new FileReader.open(args.shift)
 	end
 
 	# The next line to process by the main program
diff --git a/lib/ordered_tree.nit b/lib/ordered_tree.nit
index 5c42f46..b507fb3 100644
--- a/lib/ordered_tree.nit
+++ b/lib/ordered_tree.nit
@@ -59,7 +59,7 @@ module ordered_tree
 # This class can be used as it to work with generic trees but can also be specialized to provide more specific
 # behavior or display. It is why the internal attributes are mutable.
 class OrderedTree[E: Object]
-	super Streamable
+	super Writable
 	super Collection[E]
 
 	# The roots of the tree (in sequence)
@@ -85,7 +85,7 @@ class OrderedTree[E: Object]
 
 	# print the full tree on `o`
 	# Write a ASCII-style tree and use the `display` method to label elements
-	redef fun write_to(stream: OStream)
+	redef fun write_to(stream: Writer)
 	do
 		for r in roots do
 			stream.write display(r)
@@ -94,7 +94,7 @@ class OrderedTree[E: Object]
 		end
 	end
 
-	private fun sub_write_to(o: OStream, e: E, prefix: String)
+	private fun sub_write_to(o: Writer, e: E, prefix: String)
 	do
 		if not sub.has_key(e) then return
 		var subs = sub[e]
diff --git a/lib/pnacl.nit b/lib/pnacl.nit
index 70b8e7c..516c860 100644
--- a/lib/pnacl.nit
+++ b/lib/pnacl.nit
@@ -630,9 +630,9 @@ end
 
 # A stream for PNaCl, redefines basic input and output methods.
 class PnaclStream
-	super PollableIStream
-	super OStream
-	super BufferedIStream
+	super PollableReader
+	super Writer
+	super BufferedReader
 
 	init do prepare_buffer(10)
 
diff --git a/lib/poset.nit b/lib/poset.nit
index 568f968..93afcf1 100644
--- a/lib/poset.nit
+++ b/lib/poset.nit
@@ -228,7 +228,7 @@ class POSet[E]
 	#
 	# Nodes are labeled with their `to_s` so homonymous nodes may appear.
 	# Edges are unlabeled.
-	fun write_dot(f: OStream)
+	fun write_dot(f: Writer)
 	do
 		f.write "digraph \{\n"
 		var ids = new HashMap[E, Int]
@@ -258,7 +258,7 @@ class POSet[E]
 	# See `write_dot` for details.
 	fun show_dot
 	do
-		var f = new OProcess("dot", "-Txlib")
+		var f = new ProcessWriter("dot", "-Txlib")
 		write_dot(f)
 		f.close
 		f.wait
diff --git a/lib/sax/input_source.nit b/lib/sax/input_source.nit
index cdf7afb..0427f4a 100644
--- a/lib/sax/input_source.nit
+++ b/lib/sax/input_source.nit
@@ -58,7 +58,7 @@ class InputSource
 	# resolving relative URIs, may use `public_id=` to include a public
 	# identifier, and may use `encoding=` to specify the object's character
 	# encoding.
-	init with_stream(stream: IStream) do
+	init with_stream(stream: Reader) do
 		self.stream = stream
 	end
 
@@ -84,7 +84,7 @@ class InputSource
 	# for resolving relative URIs, may set `public_id` to include a
 	# public identifier, and may set `encoding` to specify the object's
 	# character encoding.
-	var stream: nullable IStream = null is writable
+	var stream: nullable Reader = null is writable
 
 	# The character encoding, if known.
 	#
diff --git a/lib/saxophonit/lexer.nit b/lib/saxophonit/lexer.nit
index 289d7fe..f95e5e3 100644
--- a/lib/saxophonit/lexer.nit
+++ b/lib/saxophonit/lexer.nit
@@ -25,7 +25,7 @@ class XophonLexer
 	var reader_model: XophonReaderModel
 
 	# The input to read from.
-	var input: IStream is writable
+	var input: Reader is writable
 
 	# Alias to `reader_model.locator`.
 	private var locator: SAXLocatorImpl is noinit
diff --git a/lib/saxophonit/saxophonit.nit b/lib/saxophonit/saxophonit.nit
index 1073b4d..6b3f616 100644
--- a/lib/saxophonit/saxophonit.nit
+++ b/lib/saxophonit/saxophonit.nit
@@ -60,7 +60,7 @@ private import lexer
 #     var reader = new XophonReader
 #     #
 #     reader.content_handler = text
-#     reader.parse(new InputSource.with_stream(new StringIStream("<foo>bar baz <n>42</n>.</foo>")))
+#     reader.parse(new InputSource.with_stream(new StringReader("<foo>bar baz <n>42</n>.</foo>")))
 #     assert text.to_s == "bar baz 42."
 class XophonReader
 	super XMLReader
@@ -147,7 +147,7 @@ class XophonReader
 				model.fire_fatal_error("File <{input.system_id.as(not null)}> not found.", null)
 			else
 				lexer = new XophonLexer(model,
-						new IFStream.open(system_id.value))
+						new FileReader.open(system_id.value))
 				parse_main
 				lexer.close
 			end
diff --git a/lib/saxophonit/testing.nit b/lib/saxophonit/testing.nit
index 1987d8c..70db6a5 100644
--- a/lib/saxophonit/testing.nit
+++ b/lib/saxophonit/testing.nit
@@ -588,6 +588,6 @@ abstract class SAXTestSuite
 
 	# Make the reader parse the specified string
 	fun parse_string(str: String) do
-		actual.parse(new InputSource.with_stream(new StringIStream(str)))
+		actual.parse(new InputSource.with_stream(new StringReader(str)))
 	end
 end
diff --git a/lib/sendmail.nit b/lib/sendmail.nit
index 0040c71..72b8ea3 100644
--- a/lib/sendmail.nit
+++ b/lib/sendmail.nit
@@ -74,7 +74,7 @@ class Mail
 		all.add_all cc
 		all.add_all bcc
 
-		var proc = new OProcess("sendmail", all.join(","))
+		var proc = new ProcessWriter("sendmail", all.join(","))
 		if proc.is_writable then proc.write to_s
 		proc.close
 		proc.wait
diff --git a/lib/socket/socket.nit b/lib/socket/socket.nit
index d9bc5a3..42c7e00 100644
--- a/lib/socket/socket.nit
+++ b/lib/socket/socket.nit
@@ -41,9 +41,9 @@ end
 # Simple communication stream with a remote socket
 class TCPStream
 	super Socket
-	super BufferedIStream
-	super OStream
-	super PollableIStream
+	super BufferedReader
+	super Writer
+	super PollableReader
 
 	# Real canonical name of the host to which `self` is connected
 	var host: String
diff --git a/lib/standard/exec.nit b/lib/standard/exec.nit
index 79f9bfd..13cd7a0 100644
--- a/lib/standard/exec.nit
+++ b/lib/standard/exec.nit
@@ -88,12 +88,12 @@ class Process
 end
 
 # stdout of the process is readable
-class IProcess
+class ProcessReader
 	super Process
-	super IStream
+	super Reader
 
 	# File Descriptor used for the input.
-	var stream_in: IFStream is noinit
+	var stream_in: FileReader is noinit
 
 	redef fun close do stream_in.close
 
@@ -106,17 +106,17 @@ class IProcess
 	redef fun execute
 	do
 		super
-		stream_in = new IFStream.from_fd(data.out_fd)
+		stream_in = new FileReader.from_fd(data.out_fd)
 	end
 end
 
 # stdin of the process is writable
-class OProcess
+class ProcessWriter
 	super Process
-	super OStream
+	super Writer
 
 	# File Descriptor used for the output.
-	var stream_out: OStream is noinit
+	var stream_out: Writer is noinit
 
 	redef fun close do stream_out.close
 
@@ -129,15 +129,15 @@ class OProcess
 	redef fun execute
 	do
 		super
-		stream_out = new OFStream.from_fd(data.in_fd)
+		stream_out = new FileWriter.from_fd(data.in_fd)
 	end
 end
 
 # stdin and stdout are both accessible
-class IOProcess
-	super IProcess
-	super OProcess
-	super IOStream
+class ProcessDuplex
+	super ProcessReader
+	super ProcessWriter
+	super Duplex
 
 	redef fun close
 	do
diff --git a/lib/standard/file.nit b/lib/standard/file.nit
index 52bfbd7..a777028 100644
--- a/lib/standard/file.nit
+++ b/lib/standard/file.nit
@@ -33,8 +33,8 @@ in "C Header" `{
 `}
 
 # File Abstract Stream
-abstract class FStream
-	super IOS
+abstract class FileStream
+	super Stream
 	# The path of the file.
 	var path: nullable String = null
 
@@ -47,7 +47,7 @@ abstract class FStream
 	# File descriptor of this file
 	fun fd: Int do return _file.fileno
 
-	# Sets the buffering mode for the current FStream
+	# Sets the buffering mode for the current FileStream
 	#
 	# If the buf_size is <= 0, its value will be 512 by default
 	#
@@ -58,16 +58,16 @@ abstract class FStream
 	fun set_buffering_mode(buf_size, mode: Int) do
 		if buf_size <= 0 then buf_size = 512
 		if _file.set_buffering_type(buf_size, mode) != 0 then
-			last_error = new IOError("Error while changing buffering type for FStream, returned error {sys.errno.strerror}")
+			last_error = new IOError("Error while changing buffering type for FileStream, returned error {sys.errno.strerror}")
 		end
 	end
 end
 
 # File input stream
-class IFStream
-	super FStream
-	super BufferedIStream
-	super PollableIStream
+class FileReader
+	super FileStream
+	super BufferedReader
+	super PollableReader
 	# Misc
 
 	# Open the same file again.
@@ -134,9 +134,9 @@ class IFStream
 end
 
 # File output stream
-class OFStream
-	super FStream
-	super OStream
+class FileWriter
+	super FileStream
+	super Writer
 
 	redef fun write(s)
 	do
@@ -236,7 +236,7 @@ private fun wipe_write: NativeString do return "w".to_cstring
 
 # Standard input stream.
 class Stdin
-	super IFStream
+	super FileReader
 
 	init do
 		_file = new NativeFile.native_stdin
@@ -249,7 +249,7 @@ end
 
 # Standard output stream.
 class Stdout
-	super OFStream
+	super FileWriter
 	init do
 		_file = new NativeFile.native_stdout
 		path = "/dev/stdout"
@@ -259,7 +259,7 @@ end
 
 # Standard error stream.
 class Stderr
-	super OFStream
+	super FileWriter
 	init do
 		_file = new NativeFile.native_stderr
 		path = "/dev/stderr"
@@ -269,11 +269,11 @@ end
 
 ###############################################################################
 
-redef class Streamable
+redef class Writable
 	# Like `write_to` but take care of creating the file
 	fun write_to_file(filepath: String)
 	do
-		var stream = new OFStream.open(filepath)
+		var stream = new FileWriter.open(filepath)
 		write_to(stream)
 		stream.close
 	end
@@ -354,19 +354,19 @@ class Path
 	# Open this file for reading
 	#
 	# Require: `exists and not link_stat.is_dir`
-	fun open_ro: IFStream
+	fun open_ro: FileReader
 	do
 		# TODO manage streams error when they are merged
-		return new IFStream.open(path)
+		return new FileReader.open(path)
 	end
 
 	# Open this file for writing
 	#
 	# Require: `not exists or not stat.is_dir`
-	fun open_wo: OFStream
+	fun open_wo: FileWriter
 	do
 		# TODO manage streams error when they are merged
-		return new OFStream.open(path)
+		return new FileWriter.open(path)
 	end
 
 	# Read all the content of the file
@@ -376,7 +376,7 @@ class Path
 	# print content
 	# ~~~
 	#
-	# See `IStream::read_all` for details.
+	# See `Reader::read_all` for details.
 	fun read_all: String
 	do
 		var s = open_ro
@@ -398,7 +398,7 @@ class Path
 	# end
 	# ~~~
 	#
-	# See `IStream::read_lines` for details.
+	# See `Reader::read_lines` for details.
 	fun read_lines: Array[String]
 	do
 		var s = open_ro
@@ -418,7 +418,7 @@ class Path
 	#
 	# Note: the stream is automatically closed at the end of the file (see `LineIterator::close_on_finish`)
 	#
-	# See `IStream::each_line` for details.
+	# See `Reader::each_line` for details.
 	fun each_line: LineIterator
 	do
 		var s = open_ro
@@ -999,17 +999,17 @@ end
 redef class Sys
 
 	init do
-		if stdout isa FStream then stdout.as(FStream).set_buffering_mode(256, buffer_mode_line)
+		if stdout isa FileStream then stdout.as(FileStream).set_buffering_mode(256, buffer_mode_line)
 	end
 
 	# Standard input
-	var stdin: PollableIStream = new Stdin is protected writable
+	var stdin: PollableReader = new Stdin is protected writable
 
 	# Standard output
-	var stdout: OStream = new Stdout is protected writable
+	var stdout: Writer = new Stdout is protected writable
 
 	# Standard output for errors
-	var stderr: OStream = new Stderr is protected writable
+	var stderr: Writer = new Stderr is protected writable
 
 	# Enumeration for buffer mode full (flushes when buffer is full)
 	fun buffer_mode_full: Int is extern "file_Sys_Sys_buffer_mode_full_0"
@@ -1020,15 +1020,15 @@ redef class Sys
 
 	# returns first available stream to read or write to
 	# return null on interruption (possibly a signal)
-	protected fun poll( streams : Sequence[FStream] ) : nullable FStream
+	protected fun poll( streams : Sequence[FileStream] ) : nullable FileStream
 	do
 		var in_fds = new Array[Int]
 		var out_fds = new Array[Int]
-		var fd_to_stream = new HashMap[Int,FStream]
+		var fd_to_stream = new HashMap[Int,FileStream]
 		for s in streams do
 			var fd = s.fd
-			if s isa IFStream then in_fds.add( fd )
-			if s isa OFStream then out_fds.add( fd )
+			if s isa FileReader then in_fds.add( fd )
+			if s isa FileWriter then out_fds.add( fd )
 
 			fd_to_stream[fd] = s
 		end
diff --git a/lib/standard/stream.nit b/lib/standard/stream.nit
index ddc01fe..24681fe 100644
--- a/lib/standard/stream.nit
+++ b/lib/standard/stream.nit
@@ -26,10 +26,10 @@ class IOError
 end
 
 # Abstract stream class
-abstract class IOS
+abstract class Stream
 	# Error produced by the file stream
 	#
-	#     var ifs = new IFStream.open("donotmakethisfile.binx")
+	#     var ifs = new FileReader.open("donotmakethisfile.binx")
 	#     ifs.read_all
 	#     ifs.close
 	#     assert ifs.last_error != null
@@ -40,8 +40,8 @@ abstract class IOS
 end
 
 # Abstract input streams
-abstract class IStream
-	super IOS
+abstract class Reader
+	super Stream
 	# Read a character. Return its ASCII value, -1 on EOF or timeout
 	fun read_char: Int is abstract
 
@@ -66,7 +66,7 @@ abstract class IStream
 	#
 	# ~~~
 	# var txt = "Hello\n\nWorld\n"
-	# var i = new StringIStream(txt)
+	# var i = new StringReader(txt)
 	# assert i.read_line == "Hello"
 	# assert i.read_line == ""
 	# assert i.read_line == "World"
@@ -79,7 +79,7 @@ abstract class IStream
 	#
 	# ~~~
 	# var txt2 = "Hello\r\n\n\rWorld"
-	# var i2 = new StringIStream(txt2)
+	# var i2 = new StringReader(txt2)
 	# assert i2.read_line == "Hello"
 	# assert i2.read_line == ""
 	# assert i2.read_line == "\rWorld"
@@ -102,7 +102,7 @@ abstract class IStream
 	#
 	# ~~~
 	# var txt = "Hello\n\nWorld\n"
-	# var i = new StringIStream(txt)
+	# var i = new StringReader(txt)
 	# assert i.read_lines == ["Hello", "", "World"]
 	# ~~~
 	#
@@ -126,7 +126,7 @@ abstract class IStream
 	#
 	# ~~~
 	# var txt = "Hello\n\nWorld\n"
-	# var i = new StringIStream(txt)
+	# var i = new StringReader(txt)
 	# assert i.each_line.to_a == ["Hello", "", "World"]
 	# ~~~
 	#
@@ -134,7 +134,7 @@ abstract class IStream
 	# Therefore, the stream should no be closed until the end of the stream.
 	#
 	# ~~~
-	# i = new StringIStream(txt)
+	# i = new StringReader(txt)
 	# var el = i.each_line
 	#
 	# assert el.item == "Hello"
@@ -155,7 +155,7 @@ abstract class IStream
 	#
 	# ~~~
 	# var txt = "Hello\n\nWorld\n"
-	# var i = new StringIStream(txt)
+	# var i = new StringReader(txt)
 	# assert i.read_all == txt
 	# ~~~
 	fun read_all: String
@@ -177,7 +177,7 @@ abstract class IStream
 	#
 	# ~~~
 	# var txt = "Hello\n\nWorld\n"
-	# var i = new StringIStream(txt)
+	# var i = new StringReader(txt)
 	# var b = new FlatBuffer
 	# i.append_line_to(b)
 	# assert b == "Hello\n"
@@ -192,7 +192,7 @@ abstract class IStream
 	# a non-eol terminated last line was returned.
 	#
 	# ~~~
-	# var i2 = new StringIStream("hello")
+	# var i2 = new StringReader("hello")
 	# assert not i2.eof
 	# var b2 = new FlatBuffer
 	# i2.append_line_to(b2)
@@ -222,13 +222,13 @@ abstract class IStream
 	fun eof: Bool is abstract
 end
 
-# Iterator returned by `IStream::each_line`.
+# Iterator returned by `Reader::each_line`.
 # See the aforementioned method for details.
 class LineIterator
 	super Iterator[String]
 
 	# The original stream
-	var stream: IStream
+	var stream: Reader
 
 	redef fun is_ok
 	do
@@ -269,9 +269,9 @@ class LineIterator
 	end
 end
 
-# IStream capable of declaring if readable without blocking
-abstract class PollableIStream
-	super IStream
+# `ReadStream` capable of declaring if readable without blocking
+abstract class PollableReader
+	super Reader
 
 	# Is there something to read? (without blocking)
 	fun poll_in: Bool is abstract
@@ -279,8 +279,8 @@ abstract class PollableIStream
 end
 
 # Abstract output stream
-abstract class OStream
-	super IOS
+abstract class Writer
+	super Stream
 	# write a string
 	fun write(s: Text) is abstract
 
@@ -288,16 +288,16 @@ abstract class OStream
 	fun is_writable: Bool is abstract
 end
 
-# Things that can be efficienlty writen to a OStream
+# Things that can be efficienlty writen to a `WriteStream`
 #
 # The point of this interface it to allow is instance to be efficenty
-# writen into a OStream without having to allocate a big String object
+# writen into a `WriteStream` without having to allocate a big String object
 #
 # ready-to-save documents usually provide this interface.
-interface Streamable
+interface Writable
 	# Write itself to a `stream`
 	# The specific logic it let to the concrete subclasses
-	fun write_to(stream: OStream) is abstract
+	fun write_to(stream: Writer) is abstract
 
 	# Like `write_to` but return a new String (may be quite large)
 	#
@@ -306,20 +306,20 @@ interface Streamable
 	# stream without having to allocate and concatenate strings
 	fun write_to_string: String
 	do
-		var stream = new StringOStream
+		var stream = new StringWriter
 		write_to(stream)
 		return stream.to_s
 	end
 end
 
 redef class Text
-	super Streamable
+	super Writable
 	redef fun write_to(stream) do stream.write(self)
 end
 
 # Input streams with a buffer
-abstract class BufferedIStream
-	super IStream
+abstract class BufferedReader
+	super Reader
 	redef fun read_char
 	do
 		if last_error != null then return -1
@@ -440,16 +440,16 @@ abstract class BufferedIStream
 end
 
 # An Input/Output Stream
-abstract class IOStream
-	super IStream
-	super OStream
+abstract class Duplex
+	super Reader
+	super Writer
 end
 
 # Stream to a String.
 #
-# Mainly used for compatibility with OStream type and tests.
-class StringOStream
-	super OStream
+# Mainly used for compatibility with Writer type and tests.
+class StringWriter
+	super Writer
 
 	private var content = new Array[String]
 	redef fun to_s do return content.to_s
@@ -468,9 +468,9 @@ end
 
 # Stream from a String.
 #
-# Mainly used for compatibility with IStream type and tests.
-class StringIStream
-	super IStream
+# Mainly used for compatibility with Reader type and tests.
+class StringReader
+	super Reader
 
 	# The string to read from.
 	var source: String
diff --git a/lib/string_experimentations/utf8.nit b/lib/string_experimentations/utf8.nit
index f5b8786..ec66af6 100644
--- a/lib/string_experimentations/utf8.nit
+++ b/lib/string_experimentations/utf8.nit
@@ -412,7 +412,7 @@ redef class NativeString
 	end
 end
 
-redef class OFStream
+redef class FileWriter
 	redef fun write(s)
 	do
 		assert is_writable
diff --git a/lib/string_experimentations/utf8_noindex.nit b/lib/string_experimentations/utf8_noindex.nit
index 547cbf7..0fa637a 100644
--- a/lib/string_experimentations/utf8_noindex.nit
+++ b/lib/string_experimentations/utf8_noindex.nit
@@ -731,7 +731,7 @@ redef class NativeString
 	end
 end
 
-redef class OFStream
+redef class FileWriter
 	redef fun write(s)
 	do
 		assert is_writable
diff --git a/lib/template/macro.nit b/lib/template/macro.nit
index 3042519..441f101 100644
--- a/lib/template/macro.nit
+++ b/lib/template/macro.nit
@@ -28,7 +28,7 @@ import template
 # using macros and replacement.
 #
 # A macro is represented as a string identifier like `%MACRO%` in the template
-# string. Using `TemplateString`, macros can be replaced by any `Streamable` data:
+# string. Using `TemplateString`, macros can be replaced by any `Writable` data:
 #
 #    var tpl = new TemplateString("Hello %NAME%!")
 #    tpl.replace("NAME", "Dave")
@@ -139,7 +139,7 @@ class TemplateString
 
 	# Loads the template file contents.
 	private fun load_template_file(tpl_file: String): String do
-		var file = new IFStream.open(tpl_file)
+		var file = new FileReader.open(tpl_file)
 		var text = file.read_all
 		file.close
 		return text
@@ -216,7 +216,7 @@ class TemplateString
 	#    var tpl = new TemplateString("Hello %NAME%!")
 	#    tpl.replace("NAME", "Dave")
 	#    assert tpl.write_to_string == "Hello Dave!"
-	fun replace(name: String, replacement: Streamable) do
+	fun replace(name: String, replacement: Writable) do
 		assert has_macro(name)
 		for macro in macros[name] do
 			macro.replacement = replacement
@@ -269,7 +269,7 @@ class TemplateString
 	#    tpl.replace("FIRSTNAME", "Corben")
 	#    tpl.replace("LASTNAME", "Dallas")
 	#    for name, rep in tpl do assert rep != null
-	fun iterator: MapIterator[String, nullable Streamable] do
+	fun iterator: MapIterator[String, nullable Writable] do
 		return new TemplateStringIterator(self)
 	end
 end
@@ -287,7 +287,7 @@ private class TemplateMacro
 	var end_pos: Int
 
 	# Macro replacement if any.
-	var replacement: nullable Streamable = null
+	var replacement: nullable Writable = null
 
 	# Does `self` already have a `replacement`?
 	fun is_replaced: Bool do return replacement != null
@@ -360,7 +360,7 @@ redef class String
 end
 
 private class TemplateStringIterator
-	super MapIterator[String, nullable Streamable]
+	super MapIterator[String, nullable Writable]
 
 	var subject: TemplateString
 	var key_it: Iterator[String] is noinit
diff --git a/lib/template/template.nit b/lib/template/template.nit
index a6acb92..b67df17 100644
--- a/lib/template/template.nit
+++ b/lib/template/template.nit
@@ -39,7 +39,7 @@ module template
 #
 # # Non-linear system with sub-templates.
 #
-# A template is made of a mix of string, sub-templates and other `Streamable` objects.
+# A template is made of a mix of string, sub-templates and other `Writable` objects.
 # A sub-template can be constructed independently of its usages, thus simplifying
 # the high-level logic.
 # A single sub-template can be used more than once.
@@ -67,7 +67,7 @@ module template
 #
 #     class LnkTmpl
 #         super Template
-#         var text: Streamable
+#         var text: Writable
 #         var title: nullable String
 #         var href: String
 #         redef fun rendering do
@@ -83,7 +83,7 @@ module template
 #     assert l.write_to_string == """<a href="hello.png">hello world</a>"""
 #
 class Template
-	super Streamable
+	super Writable
 
 	# Service used to render the content of the template.
 	#
@@ -106,7 +106,7 @@ class Template
 	#     t.add("1")
 	#     t.add("2")
 	#     assert t.write_to_string == "12"
-	fun add(element: Streamable) do
+	fun add(element: Writable) do
 		assert not is_frozen
 		content.add element
 	end
@@ -117,7 +117,7 @@ class Template
 	#     t.addn("1")
 	#     t.addn("2")
 	#     assert t.write_to_string == "1\n2\n"
-	fun addn(element: Streamable) do
+	fun addn(element: Writable) do
 		add element
 		add "\n"
 	end
@@ -128,7 +128,7 @@ class Template
 	#     var t = new Template
 	#     t.add_all(["1", "2"])
 	#     assert t.write_to_string == "12"
-	fun add_all(elements: Collection[Streamable]) do content.add_all elements
+	fun add_all(elements: Collection[Writable]) do content.add_all elements
 
 	# Append a bunch of elements at the end of the template with separations.
 	# see `add`.
@@ -136,7 +136,7 @@ class Template
 	#      var t = new Template
 	#      t.add_list(["1", "2", "3"], ", ", " and ")
 	#      assert t.write_to_string == "1, 2 and 3"
-	fun add_list(elements: Collection[Streamable], sep, last_sep: Streamable) do
+	fun add_list(elements: Collection[Writable], sep, last_sep: Writable) do
 		var last = elements.length - 2
 		var i = 0
 		for e in elements do
@@ -181,7 +181,7 @@ class Template
 	end
 
 	# Each sub-elements
-	private var content = new Array[Streamable]
+	private var content = new Array[Writable]
 
 	# Flag to avoid multiple rendering
 	private var render_done = false
@@ -200,7 +200,7 @@ class Template
 	end
 
 	# Do the full rendering and write the final content to a stream
-	redef fun write_to(stream: OStream)
+	redef fun write_to(stream: Writer)
 	do
 		assert not is_writing
 		is_writing = true
diff --git a/lib/trees/bintree.nit b/lib/trees/bintree.nit
index d11898f..6b6b91c 100644
--- a/lib/trees/bintree.nit
+++ b/lib/trees/bintree.nit
@@ -339,7 +339,7 @@ class BinTreeMap[K: Comparable, E]
 
 	redef fun show_dot do
 		assert not_empty: root != null
-		var f = new OProcess("dot", "-Txlib")
+		var f = new ProcessWriter("dot", "-Txlib")
 		f.write "digraph \{\n"
 		dot_down(root.as(not null), f)
 		f.write "\}\n"
@@ -347,7 +347,7 @@ class BinTreeMap[K: Comparable, E]
 	end
 
 	# Translate the tree in dot format starting from `node`.
-	protected fun dot_down(node: N, f: OProcess) do
+	protected fun dot_down(node: N, f: ProcessWriter) do
 		if node.left != null then dot_down(node.left.as(not null), f)
 		f.write node.to_dot
 		if node.right != null then dot_down(node.right.as(not null), f)
diff --git a/src/c_tools.nit b/src/c_tools.nit
index 6fa1f05..932f03d 100644
--- a/src/c_tools.nit
+++ b/src/c_tools.nit
@@ -61,7 +61,7 @@ class CCompilationUnit
 		body_impl.add( efc.to_writer )
 	end
 
-	fun compile_header_core( stream : OStream )
+	fun compile_header_core( stream : Writer )
 	do
 		header_c_base.write_to( stream )
 		header_custom.write_to( stream )
@@ -69,7 +69,7 @@ class CCompilationUnit
 		header_decl.write_to( stream )
 	end
 
-	fun compile_body_core( stream : OStream )
+	fun compile_body_core( stream : Writer )
 	do
 		body_decl.write_to( stream )
 		body_custom.write_to( stream )
diff --git a/src/compiler/abstract_compiler.nit b/src/compiler/abstract_compiler.nit
index f286f02..01de936 100644
--- a/src/compiler/abstract_compiler.nit
+++ b/src/compiler/abstract_compiler.nit
@@ -212,7 +212,7 @@ class MakefileToolchain
 
 		var hfilename = compiler.header.file.name + ".h"
 		var hfilepath = "{compile_dir}/{hfilename}"
-		var h = new OFStream.open(hfilepath)
+		var h = new FileWriter.open(hfilepath)
 		for l in compiler.header.decl_lines do
 			h.write l
 			h.write "\n"
@@ -227,7 +227,7 @@ class MakefileToolchain
 		for f in compiler.files do
 			var i = 0
 			var count = 0
-			var file: nullable OFStream = null
+			var file: nullable FileWriter = null
 			for vis in f.writers do
 				if vis == compiler.header then continue
 				var total_lines = vis.lines.length + vis.decl_lines.length
@@ -240,7 +240,7 @@ class MakefileToolchain
 					var cfilepath = "{compile_dir}/{cfilename}"
 					self.toolcontext.info("new C source files to compile: {cfilepath}", 3)
 					cfiles.add(cfilename)
-					file = new OFStream.open(cfilepath)
+					file = new FileWriter.open(cfilepath)
 					file.write "#include \"{f.name}.0.h\"\n"
 					count = total_lines
 				end
@@ -258,8 +258,8 @@ class MakefileToolchain
 
 			var cfilename = "{f.name}.0.h"
 			var cfilepath = "{compile_dir}/{cfilename}"
-			var hfile: nullable OFStream = null
-			hfile = new OFStream.open(cfilepath)
+			var hfile: nullable FileWriter = null
+			hfile = new FileWriter.open(cfilepath)
 			hfile.write "#include \"{hfilename}\"\n"
 			for key in f.required_declarations do
 				if not compiler.provided_declarations.has_key(key) then
@@ -321,7 +321,7 @@ class MakefileToolchain
 		end
 		var makename = makefile_name(mainmodule)
 		var makepath = "{compile_dir}/{makename}"
-		var makefile = new OFStream.open(makepath)
+		var makefile = new FileWriter.open(makepath)
 
 		var linker_options = new HashSet[String]
 		for m in mainmodule.in_importation.greaters do
@@ -371,7 +371,7 @@ class MakefileToolchain
 		if not compiler.linker_script.is_empty then
 			var linker_script_path = "{compile_dir}/linker_script"
 			ofiles.add "linker_script"
-			var f = new OFStream.open(linker_script_path)
+			var f = new FileWriter.open(linker_script_path)
 			for l in compiler.linker_script do
 				f.write l
 				f.write "\n"
@@ -546,7 +546,7 @@ abstract class AbstractCompiler
 	do
 		var compile_dir = modelbuilder.compile_dir
 
-		var stream = new OFStream.open("{compile_dir}/c_functions_hash.c")
+		var stream = new FileWriter.open("{compile_dir}/c_functions_hash.c")
 		stream.write("#include <string.h>\n")
 		stream.write("#include <stdlib.h>\n")
 		stream.write("#include \"c_functions_hash.h\"\n")
@@ -576,7 +576,7 @@ abstract class AbstractCompiler
 		stream.write("\}\n")
 		stream.close
 
-		stream = new OFStream.open("{compile_dir}/c_functions_hash.h")
+		stream = new FileWriter.open("{compile_dir}/c_functions_hash.h")
 		stream.write("const char* get_nit_name(register const char* procname, register unsigned int len);\n")
 		stream.close
 
diff --git a/src/doc/doc_down.nit b/src/doc/doc_down.nit
index 1cdc51a..60ed50b 100644
--- a/src/doc/doc_down.nit
+++ b/src/doc/doc_down.nit
@@ -27,7 +27,7 @@ redef class MDoc
 	var full_comment: String is lazy do return content.join("\n").html_escape
 
 	# Synopsys in a template
-	var tpl_short_comment: Streamable is lazy do
+	var tpl_short_comment: Writable is lazy do
 		var res = new Template
 		var syn = nitdoc_inline_processor.process(content.first)
 		res.add "<span class=\"synopsys nitdoc\">{syn}</span>"
@@ -36,7 +36,7 @@ redef class MDoc
 	end
 
 	# Full comment in a template
-	var tpl_comment: Streamable is lazy do
+	var tpl_comment: Writable is lazy do
 		var res = new Template
 		var lines = content.to_a
 		res.add "<div class=\"nitdoc\">"
diff --git a/src/doc/doc_phases/doc_html.nit b/src/doc/doc_phases/doc_html.nit
index a4bdeb0..e4865e5 100644
--- a/src/doc/doc_phases/doc_html.nit
+++ b/src/doc/doc_phases/doc_html.nit
@@ -818,11 +818,11 @@ redef class GraphArticle
 		var output_dir = v.ctx.output_dir
 		var path = output_dir / id
 		var path_sh = path.escape_to_sh
-		var file = new OFStream.open("{path}.dot")
+		var file = new FileWriter.open("{path}.dot")
 		file.write(dot)
 		file.close
 		sys.system("\{ test -f {path_sh}.png && test -f {path_sh}.s.dot && diff -- {path_sh}.dot {path_sh}.s.dot >/dev/null 2>&1 ; \} || \{ cp -- {path_sh}.dot {path_sh}.s.dot && dot -Tpng -o{path_sh}.png -Tcmapx -o{path_sh}.map {path_sh}.s.dot ; \}")
-		var fmap = new IFStream.open("{path}.map")
+		var fmap = new FileReader.open("{path}.map")
 		var map = fmap.read_all
 		fmap.close
 
diff --git a/src/doc/doc_templates.nit b/src/doc/doc_templates.nit
index cbb625e..c23e880 100644
--- a/src/doc/doc_templates.nit
+++ b/src/doc/doc_templates.nit
@@ -45,7 +45,7 @@ class TplPage
 	var sections = new Array[TplSection]
 
 	# Footer content if any
-	var footer: nullable Streamable = null is writable
+	var footer: nullable Writable = null is writable
 
 	# JS scripts to append at the end of the body
 	var scripts = new Array[TplScript]
@@ -158,9 +158,9 @@ class TplTopMenu
 	super Template
 
 	# Brand link to display in first position of the top menu
-	private var brand: nullable Streamable = null is writable
+	private var brand: nullable Writable = null is writable
 	# Elements of the topmenu
-	private var elts = new Array[Streamable]
+	private var elts = new Array[Writable]
 
 	# The page url where the top menu is displayed.
 	#
@@ -174,7 +174,7 @@ class TplTopMenu
 	end
 
 	# Add a content between `<li>` tags
-	fun add_item(content: Streamable, is_active: Bool) do
+	fun add_item(content: Writable, is_active: Bool) do
 		var tpl = new Template
 		tpl.add "<li"
 		if is_active then
@@ -187,7 +187,7 @@ class TplTopMenu
 	end
 
 	# Add a raw content to the menu
-	fun add_raw(content: Streamable) do
+	fun add_raw(content: Writable) do
 		elts.add content
 	end
 
@@ -277,7 +277,7 @@ class TplSideBox
 
 	# Content to display in the box
 	# box will not be rendered if the content is null
-	var content: nullable Streamable = null is writable
+	var content: nullable Writable = null is writable
 
 	# Is the box opened by default
 	# otherwise, the user will have to clic on the title to display the content
@@ -287,7 +287,7 @@ class TplSideBox
 		self.id = title.to_cmangle
 	end
 
-	init with_content(title: String, content: Streamable) do
+	init with_content(title: String, content: Writable) do
 		init(title)
 		self.content = content
 	end
@@ -352,7 +352,7 @@ class TplSummaryEntry
 	super TplSummaryElt
 
 	# Text to display
-	var text: Streamable
+	var text: Writable
 
 	# Children of this entry
 	# Will be displayed as a tree
@@ -383,10 +383,10 @@ class TplSectionElt
 	# Title to display if any
 	# if both `title` and `summary_title` are null then
 	# the section will not appear in the summary
-	var title: nullable Streamable = null is writable
+	var title: nullable Writable = null is writable
 
 	# Subtitle to display if any
-	var subtitle: nullable Streamable = null is writable
+	var subtitle: nullable Writable = null is writable
 
 	# Title that appear in the summary
 	# if null use `title` instead
@@ -401,7 +401,7 @@ class TplSectionElt
 	# Parent article/section if any
 	var parent: nullable TplSectionElt = null
 
-	init with_title(id: String, title: Streamable) do
+	init with_title(id: String, title: Writable) do
 		init(id)
 		self.title = title
 	end
@@ -469,10 +469,10 @@ class TplArticle
 	super TplSectionElt
 
 	# Content for this article
-	var content: nullable Streamable = null is writable
-	var source_link: nullable Streamable = null is writable
+	var content: nullable Writable = null is writable
+	var source_link: nullable Writable = null is writable
 
-	init with_content(id: String, title: Streamable, content: Streamable) do
+	init with_content(id: String, title: Writable, content: Writable) do
 		with_title(id, title)
 		self.content = content
 	end
@@ -525,13 +525,13 @@ class TplDefinition
 	super Template
 
 	# Comment to display
-	var comment: nullable Streamable = null is writable
+	var comment: nullable Writable = null is writable
 
 	# Namespace for this definition
-	var namespace: nullable Streamable = null is writable
+	var namespace: nullable Writable = null is writable
 
 	# Location link to display
-	var location: nullable Streamable = null is writable
+	var location: nullable Writable = null is writable
 
 	private fun render_info do
 		addn "<div class='info text-right'>"
@@ -589,9 +589,9 @@ end
 class TplSearchPage
 	super TplSectionElt
 
-	var modules = new Array[Streamable]
-	var classes = new Array[Streamable]
-	var props = new Array[Streamable]
+	var modules = new Array[Writable]
+	var classes = new Array[Writable]
+	var props = new Array[Writable]
 
 	redef fun rendering do
 		var title = self.title
@@ -651,7 +651,7 @@ class TplLink
 	var href: String is writable
 
 	# The raw HTML content to display in the link
-	var text: Streamable is writable
+	var text: Writable is writable
 
 	# The unescaped optional title.
 	var title: nullable String = null is writable
@@ -717,16 +717,16 @@ class TplListItem
 	# CSS classes of the <li> element
 	var css_classes = new Array[String]
 
-	init with_content(content: Streamable) do append(content)
+	init with_content(content: Writable) do append(content)
 
-	init with_classes(content: Streamable, classes: Array[String]) do
+	init with_classes(content: Writable, classes: Array[String]) do
 		with_content(content)
 		css_classes = classes
 	end
 
 	# Append `content` to the item
 	# similar to `self.content.add`
-	fun append(content: Streamable) do self.content.add content
+	fun append(content: Writable) do self.content.add content
 
 	redef fun rendering do
 		add "<li class='{css_classes.join(" ")}'>"
@@ -770,16 +770,16 @@ class TplTabPanel
 	# The panel name.
 	#
 	# Displayed in the tab header or in the pointing link.
-	var name: Streamable
+	var name: Writable
 
 	# Is the panel visible by default?
 	var is_active = false is writable
 
 	# Body of the panel
-	var content: nullable Streamable = null is writable
+	var content: nullable Writable = null is writable
 
 	# Get a link pointing to this panel.
-	fun tpl_link_to: Streamable do
+	fun tpl_link_to: Writable do
 		var lnk = new Template
 		lnk.add "<a data-target='#{id}' data-toggle='pill'>"
 		lnk.add name
@@ -801,12 +801,12 @@ class TplLabel
 	super Template
 
 	# Content of the label if any
-	var content: nullable Streamable = null is writable
+	var content: nullable Writable = null is writable
 
 	# CSS classes of the <span> element
 	var css_classes = new Array[String]
 
-	init with_content(content: Streamable) do self.content = content
+	init with_content(content: Writable) do self.content = content
 	init with_classes(classes: Array[String]) do self.css_classes = classes
 
 	redef fun rendering do
@@ -867,7 +867,7 @@ class TplScript
 	super Template
 
 	var attrs = new Array[TagAttribute]
-	var content: nullable Streamable = null is writable
+	var content: nullable Writable = null is writable
 
 	init do
 		attrs.add(new TagAttribute("type", "text/javascript"))
diff --git a/src/doc/vim_autocomplete.nit b/src/doc/vim_autocomplete.nit
index 856633f..10c6bc0 100644
--- a/src/doc/vim_autocomplete.nit
+++ b/src/doc/vim_autocomplete.nit
@@ -52,7 +52,7 @@ redef class MEntity
 	private fun field_separator: String do return "#====#"
 	private fun line_separator: String do return "#nnnn#"
 
-	private fun write_to_stream(stream: OStream)
+	private fun write_to_stream(stream: Writer)
 	do
 		# 1. Short name for autocompletion
 		stream.write complete_name
@@ -82,7 +82,7 @@ redef class MEntity
 		stream.write "\n"
 	end
 
-	private fun write_signature_to_stream(stream: OStream) do end
+	private fun write_signature_to_stream(stream: Writer) do end
 
 	# Actual name used in completion
 	private fun complete_name: String do return name
@@ -159,11 +159,11 @@ private class AutocompletePhase
 		if compile_dir.is_empty then compile_dir = "HOME".environ / ".vim/nit"
 		compile_dir.mkdir
 
-		var modules_stream = new OFStream.open(compile_dir / "modules.txt")
-		var classes_stream = new OFStream.open(compile_dir / "classes.txt")
-		var constructors_stream = new OFStream.open(compile_dir / "constructors.txt")
-		var types_stream = new OFStream.open(compile_dir / "types.txt")
-		var properties_stream = new OFStream.open(compile_dir / "properties.txt")
+		var modules_stream = new FileWriter.open(compile_dir / "modules.txt")
+		var classes_stream = new FileWriter.open(compile_dir / "classes.txt")
+		var constructors_stream = new FileWriter.open(compile_dir / "constructors.txt")
+		var types_stream = new FileWriter.open(compile_dir / "types.txt")
+		var properties_stream = new FileWriter.open(compile_dir / "properties.txt")
 
 		# Got all known modules
 		var model = mainmodule.model
diff --git a/src/ffi/c_compiler_options.nit b/src/ffi/c_compiler_options.nit
index 4fbd5c4..878785c 100644
--- a/src/ffi/c_compiler_options.nit
+++ b/src/ffi/c_compiler_options.nit
@@ -101,10 +101,10 @@ private class CCompilerOptionsPhase
 				var cmd_args = opt.command
 				var proc
 				if cmd_args.length == 1 then
-					proc = new IProcess.from_a(cmd_args[0], new Array[String])
+					proc = new ProcessReader.from_a(cmd_args[0], new Array[String])
 				else if cmd_args.length > 1 then
 					var rest_args = cmd_args.subarray(1, cmd_args.length-1)
-					proc = new IProcess.from_a(cmd_args[0], rest_args)
+					proc = new ProcessReader.from_a(cmd_args[0], rest_args)
 				else abort
 
 				# wait for its completion
diff --git a/src/ffi/ffi_base.nit b/src/ffi/ffi_base.nit
index babab08..59f46b3 100644
--- a/src/ffi/ffi_base.nit
+++ b/src/ffi/ffi_base.nit
@@ -166,7 +166,7 @@ redef class CCompilationUnit
 
 	fun write_header_to_file(mmodule: MModule, file: String, includes: Array[String], guard: String)
 	do
-		var stream = new OFStream.open( file )
+		var stream = new FileWriter.open( file )
 
 		# header comments
 		var module_info = "/*\n\tExtern implementation of Nit module {mmodule.name}\n*/\n"
@@ -187,7 +187,7 @@ redef class CCompilationUnit
 
 	fun write_body_to_file(mmodule: MModule, file: String, includes: Array[String])
 	do
-		var stream = new OFStream.open(file)
+		var stream = new FileWriter.open(file)
 
 		var module_info = "/*\n\tExtern implementation of Nit module {mmodule.name}\n*/\n"
 
diff --git a/src/ffi/pkgconfig.nit b/src/ffi/pkgconfig.nit
index dca4fab..bd62de3 100644
--- a/src/ffi/pkgconfig.nit
+++ b/src/ffi/pkgconfig.nit
@@ -67,7 +67,7 @@ class PkgconfigPhase
 		end
 
 		# check availability of pkg-config
-		var proc_which = new IProcess("which", "pkg-config")
+		var proc_which = new ProcessReader("which", "pkg-config")
 		proc_which.wait
 		var status = proc_which.status
 		if status != 0 then
diff --git a/src/frontend/glsl_validation.nit b/src/frontend/glsl_validation.nit
index 5dd6b79..692d918 100644
--- a/src/frontend/glsl_validation.nit
+++ b/src/frontend/glsl_validation.nit
@@ -62,7 +62,7 @@ private class GLSLValidationPhase
 			if not in_path then return
 		else
 			# Is _glslangValidator_ installed?
-			var proc_which = new IProcess("which", "glslangValidator")
+			var proc_which = new ProcessReader("which", "glslangValidator")
 			proc_which.wait
 			proc_which.close
 			var status = proc_which.status
@@ -91,7 +91,7 @@ private class GLSLValidationPhase
 		shader.write_to_file path
 
 		# Execute the validator
-		var proc_validator = new IProcess("glslangValidator", path)
+		var proc_validator = new ProcessReader("glslangValidator", path)
 		proc_validator.wait
 		var lines = proc_validator.read_all.split('\n')
 		proc_validator.close
diff --git a/src/interpreter/debugger_socket.nit b/src/interpreter/debugger_socket.nit
index 50f98c7..828cb3b 100644
--- a/src/interpreter/debugger_socket.nit
+++ b/src/interpreter/debugger_socket.nit
@@ -115,7 +115,7 @@ redef class ModelBuilder
 end
 
 redef class Sys
-	private fun set_io(istream: PollableIStream, ostream: OStream, errstream: OStream)
+	private fun set_io(istream: PollableReader, ostream: Writer, errstream: Writer)
 	do
 		self.stdin = istream
 		self.stdout = ostream
diff --git a/src/interpreter/primitive_types.nit b/src/interpreter/primitive_types.nit
index 0de93d3..122fe4e 100644
--- a/src/interpreter/primitive_types.nit
+++ b/src/interpreter/primitive_types.nit
@@ -20,7 +20,7 @@ intrude import standard::string
 # Wrapper for `NativeFile`
 class PrimitiveNativeFile
 
-	var file: IOS
+	var file: Stream
 
 	init native_stdin do
 		file = sys.stdin
@@ -35,49 +35,49 @@ class PrimitiveNativeFile
 	end
 
 	init io_open_read(path: String) do
-		file = new IFStream.open(path.to_s)
+		file = new FileReader.open(path.to_s)
 	end
 
 	init io_open_write(path: String) do
-		file = new OFStream.open(path.to_s)
+		file = new FileWriter.open(path.to_s)
 	end
 
 	fun address_is_null: Bool do
-		if file isa FStream then return file.as(FStream)._file.address_is_null
+		if file isa FileStream then return file.as(FileStream)._file.address_is_null
 		return false
 	end
 
 	fun io_read(buf: NativeString, len: Int): Int do
-		if file isa FStream then return file.as(FStream)._file.io_read(buf, len)
-		var str = file.as(IStream).read(len)
+		if file isa FileStream then return file.as(FileStream)._file.io_read(buf, len)
+		var str = file.as(Reader).read(len)
 		str.to_cstring.copy_to(buf, str.length, 0, 0)
 		return str.length
 	end
 
 	fun io_write(buf: NativeString, len: Int): Int do
-		if file isa FStream then return file.as(FStream)._file.io_write(buf, len)
-		file.as(OStream).write(buf.to_s_with_length(len))
+		if file isa FileStream then return file.as(FileStream)._file.io_write(buf, len)
+		file.as(Writer).write(buf.to_s_with_length(len))
 		return len
 	end
 
 	fun io_close: Int do
-		if file isa FStream then return file.as(FStream)._file.io_close
+		if file isa FileStream then return file.as(FileStream)._file.io_close
 		file.close
 		return 0
 	end
 
 	fun fileno: Int do
-		if file isa FStream then return file.as(FStream)._file.fileno
+		if file isa FileStream then return file.as(FileStream)._file.fileno
 		return 0
 	end
 
 	fun flush: Int do
-		if file isa FStream then return file.as(FStream)._file.flush
+		if file isa FileStream then return file.as(FileStream)._file.flush
 		return 0
 	end
 
 	fun set_buffering_type(size, mode: Int): Int do
-		if file isa FStream then return file.as(FStream)._file.set_buffering_type(size, mode)
+		if file isa FileStream then return file.as(FileStream)._file.set_buffering_type(size, mode)
 		return 0
 	end
 end
diff --git a/src/loader.nit b/src/loader.nit
index 517deab..65e7c67 100644
--- a/src/loader.nit
+++ b/src/loader.nit
@@ -386,7 +386,7 @@ redef class ModelBuilder
 		if not readme.file_exists then readme = dirpath2.join_path("README")
 		if readme.file_exists then
 			var mdoc = new MDoc
-			var s = new IFStream.open(readme)
+			var s = new FileReader.open(readme)
 			while not s.eof do
 				mdoc.content.add(s.read_line)
 			end
@@ -430,7 +430,7 @@ redef class ModelBuilder
 		self.toolcontext.info("load module {filename}", 2)
 
 		# Load the file
-		var file = new IFStream.open(filename)
+		var file = new FileReader.open(filename)
 		var lexer = new Lexer(new SourceFile(filename, file))
 		var parser = new Parser(lexer)
 		var tree = parser.parse
diff --git a/src/location.nit b/src/location.nit
index d7154ca..83ed72f 100644
--- a/src/location.nit
+++ b/src/location.nit
@@ -26,7 +26,7 @@ class SourceFile
 	var string: String is noinit
 
 	# The original stream used to initialize `string`
-	var stream: IStream
+	var stream: Reader
 
 	init
 	do
diff --git a/src/metrics/generate_hierarchies.nit b/src/metrics/generate_hierarchies.nit
index 3522245..6193b9c 100644
--- a/src/metrics/generate_hierarchies.nit
+++ b/src/metrics/generate_hierarchies.nit
@@ -77,7 +77,7 @@ do
 		end
 	end
 	buf.append("\}\n")
-	var f = new OFStream.open(toolcontext.output_dir.join_path("class_hierarchy.dot"))
+	var f = new FileWriter.open(toolcontext.output_dir.join_path("class_hierarchy.dot"))
 	f.write(buf.to_s)
 	f.close
 end
@@ -99,7 +99,7 @@ do
 		end
 	end
 	buf.append("\}\n")
-	var f = new OFStream.open(toolcontext.output_dir.join_path("classdef_hierarchy.dot"))
+	var f = new FileWriter.open(toolcontext.output_dir.join_path("classdef_hierarchy.dot"))
 	f.write(buf.to_s)
 	f.close
 end
diff --git a/src/metrics/model_hyperdoc.nit b/src/metrics/model_hyperdoc.nit
index 43384d9..9e66e73 100644
--- a/src/metrics/model_hyperdoc.nit
+++ b/src/metrics/model_hyperdoc.nit
@@ -186,7 +186,7 @@ do
 		end
 	end
 	buf.append("</body></html>\n")
-	var f = new OFStream.open(toolcontext.output_dir.join_path("model.html"))
+	var f = new FileWriter.open(toolcontext.output_dir.join_path("model.html"))
 	f.write(buf.to_s)
 	f.close
 end
diff --git a/src/model/model_viz.nit b/src/model/model_viz.nit
index bdb8373..305cd23 100644
--- a/src/model/model_viz.nit
+++ b/src/model/model_viz.nit
@@ -136,7 +136,7 @@ end
 # Interesting elements must be selected. See `mmodules`, ``
 # Display configuration can be set. See `cluster_group`, `project_group`
 class MProjectDot
-	super Streamable
+	super Writable
 
 	# The model where to look for information
 	var model: Model
@@ -161,7 +161,7 @@ class MProjectDot
 	var project_group = true is writable
 
 	# Recursively generate node and clusters for a mgroup
-	private fun dot_cluster(o: OStream, mgroup: MGroup)
+	private fun dot_cluster(o: Writer, mgroup: MGroup)
 	do
 		# Open the cluster, if required
 		if mgroup.parent == null then
diff --git a/src/nitlight.nit b/src/nitlight.nit
index 0c8998b..5b64e3d 100644
--- a/src/nitlight.nit
+++ b/src/nitlight.nit
@@ -124,7 +124,7 @@ if dir != null then
 
 	var v = new HighlightVisitor
 	toolcontext.info("write {dir}/style.css", 1)
-	var f = new OFStream.open("{dir}/style.css")
+	var f = new FileWriter.open("{dir}/style.css")
 	f.write v.css_content
 	f.close
 end
diff --git a/src/nitls.nit b/src/nitls.nit
index 9412f5d..7ffc58c 100644
--- a/src/nitls.nit
+++ b/src/nitls.nit
@@ -144,7 +144,7 @@ var files
 if opt_recursive.value then
 	files = new Array[String]
 	for d in tc.option_context.rest do
-		var pipe = new IProcess("find", d, "-name", "*.nit")
+		var pipe = new ProcessReader("find", d, "-name", "*.nit")
 		while not pipe.eof do
 			var l = pipe.read_line
 			if l == "" then break # last line
diff --git a/src/nitpretty.nit b/src/nitpretty.nit
index 9dd723e..d759992 100644
--- a/src/nitpretty.nit
+++ b/src/nitpretty.nit
@@ -56,7 +56,7 @@ end
 
 # Return result from diff between `file1` and `file2`.
 private fun diff(file1, file2: String): String do
-	var p = new IProcess("diff", "-u", file1, file2)
+	var p = new ProcessReader("diff", "-u", file1, file2)
 	var res = p.read_all
 	p.wait
 	p.close
diff --git a/src/nitserial.nit b/src/nitserial.nit
index 4953156..98b1923 100644
--- a/src/nitserial.nit
+++ b/src/nitserial.nit
@@ -36,16 +36,16 @@ import template
 class NitModule
 	super Template
 
-	var header: nullable Streamable = null
+	var header: nullable Writable = null
 
 	# The module's name
-	var name: Streamable
+	var name: Writable
 
 	# Imports from this module
-	var imports = new Array[Streamable]
+	var imports = new Array[Writable]
 
 	# Main content of this module
-	var content = new Array[Streamable]
+	var content = new Array[Writable]
 
 	redef fun rendering
 	do
diff --git a/src/platform/android_annotations.nit b/src/platform/android_annotations.nit
index ad34b9a..484c0a6 100644
--- a/src/platform/android_annotations.nit
+++ b/src/platform/android_annotations.nit
@@ -156,7 +156,7 @@ redef class AAnnotation
 				value = arg.as_id
 				if value == "git_revision" then
 					# Get Git short revision
-					var proc = new IProcess("git", "rev-parse", "--short", "HEAD")
+					var proc = new ProcessReader("git", "rev-parse", "--short", "HEAD")
 					proc.wait
 					assert proc.status == 0
 					var lines = proc.read_all
@@ -164,7 +164,7 @@ redef class AAnnotation
 
 					# Is it dirty?
 					# If not, the return of `git diff --shortstat` is an empty line
-					proc = new IProcess("git", "diff-index", "--quiet", "HEAD")
+					proc = new ProcessReader("git", "diff-index", "--quiet", "HEAD")
 					proc.wait
 					var dirty = proc.status != 0
 					if dirty then revision += ".d"
diff --git a/src/semantize/flow.nit b/src/semantize/flow.nit
index 1f96058..b4ba420 100644
--- a/src/semantize/flow.nit
+++ b/src/semantize/flow.nit
@@ -77,7 +77,7 @@ private class FlowVisitor
 
 	fun printflow
 	do
-		var file = new OFStream.open("flow.dot")
+		var file = new FileWriter.open("flow.dot")
 		file.write("digraph \{\n")
 		for f in flows do
 			var s = ""
diff --git a/src/test_parser.nit b/src/test_parser.nit
index f654f5b..89682cc 100644
--- a/src/test_parser.nit
+++ b/src/test_parser.nit
@@ -115,7 +115,7 @@ else
 		if no_file then
 			source = new SourceFile.from_string("", a)
 		else
-			var f = new IFStream.open(a)
+			var f = new FileReader.open(a)
 			source = new SourceFile(a, f)
 			f.close
 		end
diff --git a/src/testing/testing_doc.nit b/src/testing/testing_doc.nit
index e975d85..e18eebf 100644
--- a/src/testing/testing_doc.nit
+++ b/src/testing/testing_doc.nit
@@ -144,7 +144,7 @@ class NitUnitExecutor
 		var dir = file.dirname
 		if dir != "" then dir.mkdir
 		var f
-		f = new OFStream.open(file)
+		f = new FileWriter.open(file)
 		f.write("# GENERATED FILE\n")
 		f.write("# Docunits extracted from comments\n")
 		f.write("import {mmodule.name}\n")
@@ -193,7 +193,7 @@ class NitUnitExecutor
 			var res2 = sys.system("{file.to_program_name}.bin {i} >>'{file}.out1' 2>&1 </dev/null")
 
 			var msg
-			f = new IFStream.open("{file}.out1")
+			f = new FileReader.open("{file}.out1")
 			var n2
 			n2 = new HTMLTag("system-err")
 			tc.add n2
@@ -232,7 +232,7 @@ class NitUnitExecutor
 		var dir = file.dirname
 		if dir != "" then dir.mkdir
 		var f
-		f = new OFStream.open(file)
+		f = new FileWriter.open(file)
 		f.write("# GENERATED FILE\n")
 		f.write("# Example extracted from a documentation\n")
 		f.write("import {mmodule.name}\n")
@@ -256,7 +256,7 @@ class NitUnitExecutor
 		end
 
 		var msg
-		f = new IFStream.open("{file}.out1")
+		f = new FileReader.open("{file}.out1")
 		var n2
 		n2 = new HTMLTag("system-err")
 		tc.add n2
diff --git a/src/testing/testing_gen.nit b/src/testing/testing_gen.nit
index 19532c6..5f5b82d 100644
--- a/src/testing/testing_gen.nit
+++ b/src/testing/testing_gen.nit
@@ -101,7 +101,7 @@ class NitUnitGenerator
 	var nodot: Array[String] = ["+", "-", "*", "/", "%", "==", "!=", "<", "<=", "<=>", ">", ">=", ">"]
 
 	# Generate subject init.
-	private fun gen_init(mclassdef: MClassDef): Streamable do
+	private fun gen_init(mclassdef: MClassDef): Writable do
 		if mclassdef.mclass.arity == 0 then
 			return "\t\tvar subject: {mclassdef.name}"
 		end
@@ -116,7 +116,7 @@ class NitUnitGenerator
 	end
 
 	# Generate call to `method` using `args`.
-	private fun gen_call(method: MMethodDef, args: Array[String]): Streamable do
+	private fun gen_call(method: MMethodDef, args: Array[String]): Writable do
 		# Here we handle the magic of the Nit syntax, have fun :)
 		var name = method.name
 		if name == "[]" then return "subject[{args.join(", ")}]"
diff --git a/src/testing/testing_suite.nit b/src/testing/testing_suite.nit
index 37f5c74..ad0b20a 100644
--- a/src/testing/testing_suite.nit
+++ b/src/testing/testing_suite.nit
@@ -197,7 +197,7 @@ class TestSuite
 		var include_dir = mmodule.location.file.filename.dirname
 		var cmd = "{nitg} --no-color '{file}.nit' -I {include_dir} -o '{file}.bin' > '{file}.out' 2>&1 </dev/null"
 		var res = sys.system(cmd)
-		var f = new IFStream.open("{file}.out")
+		var f = new FileReader.open("{file}.out")
 		var msg = f.read_all
 		f.close
 		# set test case result
@@ -257,7 +257,7 @@ class TestCase
 		var test_file = test_suite.test_file
 		var res_name = "{test_file}_{method_name.escape_to_c}"
 		var res = sys.system("{test_file}.bin {method_name} > '{res_name}.out1' 2>&1 </dev/null")
-		var f = new IFStream.open("{res_name}.out1")
+		var f = new FileReader.open("{res_name}.out1")
 		var msg = f.read_all
 		f.close
 		# set test case result
diff --git a/src/toolcontext.nit b/src/toolcontext.nit
index 021c2c7..a5b7ceb 100644
--- a/src/toolcontext.nit
+++ b/src/toolcontext.nit
@@ -249,7 +249,7 @@ class ToolContext
 		args.remove_at 0
 
 		# Is the wanted program available?
-		var proc_which = new IProcess.from_a("which", [prog])
+		var proc_which = new ProcessReader.from_a("which", [prog])
 		proc_which.wait
 		var res = proc_which.status
 		if res != 0 then
diff --git a/src/uml/uml_class.nit b/src/uml/uml_class.nit
index 205297f..c985a04 100644
--- a/src/uml/uml_class.nit
+++ b/src/uml/uml_class.nit
@@ -19,7 +19,7 @@ import uml_base
 
 redef class UMLModel
 	# Generates a UML class diagram from a `Model`
-	fun generate_class_uml: Streamable do
+	fun generate_class_uml: Writable do
 		var tpl = new Template
 		tpl.add "digraph G \{\n"
 		tpl.add """	fontname = "Bitstream Vera Sans"
@@ -43,7 +43,7 @@ end
 redef class Model
 
 	# Generates a UML Class diagram from the entities of a `Model`
-	fun tpl_class(ctx: ToolContext, main: MModule): Streamable do
+	fun tpl_class(ctx: ToolContext, main: MModule): Writable do
 		var t = new Template
 		for i in mclasses do
 			if not ctx.private_gen and i.visibility != public_visibility then continue
@@ -56,13 +56,13 @@ redef class Model
 end
 
 redef class MEntity
-	# Generates a dot-compatible `Streamable` UML Class diagram from `self`
-	fun tpl_class(ctx: ToolContext, main: MModule): Streamable is abstract
+	# Generates a dot-compatible `Writable` UML Class diagram from `self`
+	fun tpl_class(ctx: ToolContext, main: MModule): Writable is abstract
 end
 
 redef class MClass
 
-	redef fun tpl_class(ctx, main): Streamable do
+	redef fun tpl_class(ctx, main): Writable do
 		var t = new Template
 		t.add "{name} [\n label = \"\{"
 		if kind == abstract_kind then
@@ -174,7 +174,7 @@ redef class MVisibility
 	#
 	#    assert public_visibility.tpl_class == "+"
 	#    assert private_visibility.tpl_class == "-"
-	fun tpl_class: Streamable do
+	fun tpl_class: Writable do
 		if self == private_visibility then
 			return "-"
 		else if self == protected_visibility then
diff --git a/src/uml/uml_module.nit b/src/uml/uml_module.nit
index 8485c45..6e80325 100644
--- a/src/uml/uml_module.nit
+++ b/src/uml/uml_module.nit
@@ -20,7 +20,7 @@ import uml_class
 
 redef class UMLModel
 	# Generates a UML package diagram from a `Model`
-	fun generate_package_uml: Streamable do
+	fun generate_package_uml: Writable do
 		var tpl = new Template
 		tpl.add "digraph G \{\n"
 		tpl.add """	fontname = "Bitstream Vera Sans"
@@ -42,7 +42,7 @@ end
 
 redef class Model
 	# Returns a UML package diagram of `main`
-	fun tpl_module(ctx: ToolContext, main: MModule): Streamable do
+	fun tpl_module(ctx: ToolContext, main: MModule): Writable do
 		return main.tpl_module(ctx, main)
 	end
 end
@@ -63,7 +63,7 @@ end
 
 redef class MEntity
 	# Builds a dot UML package diagram entity from `self`
-	fun tpl_module(ctx: ToolContext, main: MModule): Streamable is abstract
+	fun tpl_module(ctx: ToolContext, main: MModule): Writable is abstract
 end
 
 redef class MClassDef
diff --git a/tests/emscripten_nodejs.nit b/tests/emscripten_nodejs.nit
index 5ada70d..2add93c 100644
--- a/tests/emscripten_nodejs.nit
+++ b/tests/emscripten_nodejs.nit
@@ -1,5 +1,5 @@
 import emscripten
-redef class IFStream
+redef class FileReader
 	redef fun fill_buffer
 	do
 		print "NOT YET IMPLEMENTED"
diff --git a/tests/sav/test_file_copy.res b/tests/sav/test_file_copy.res
index 632da3c..0d8a256 100644
--- a/tests/sav/test_file_copy.res
+++ b/tests/sav/test_file_copy.res
@@ -21,6 +21,6 @@ var src = "test_file_copy.nit"
 var dst = "{dir}/copy.nit"
 src.file_copy_to dst
 
-var file = new IFStream.open(dst)
+var file = new FileReader.open(dst)
 printn file.read_all
 file.close
diff --git a/tests/sav/test_file_read.res b/tests/sav/test_file_read.res
index cd93882..61918c0 100644
--- a/tests/sav/test_file_read.res
+++ b/tests/sav/test_file_read.res
@@ -14,7 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 var s: String
 while not f.eof do
     s = f.read_line
@@ -43,7 +43,7 @@ printn(f.read_all)
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 var s: String
 while not f.eof do
     s = f.read_line
diff --git a/tests/sav/test_file_read2.res b/tests/sav/test_file_read2.res
index d830b19..65a53af 100644
--- a/tests/sav/test_file_read2.res
+++ b/tests/sav/test_file_read2.res
@@ -14,7 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 var s: String
 while not f.eof do
     s = f.read_line
@@ -45,7 +45,7 @@ printn(f.read_all)
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 var s: String
 while not f.eof do
     s = f.read_line
@@ -75,7 +75,7 @@ printn(f.read_all)
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 var s: String
 while not f.eof do
     s = f.read_line
@@ -105,7 +105,7 @@ printn(f.read_all)
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 var s: String
 while not f.eof do
     s = f.read_line
@@ -136,7 +136,7 @@ printn(f.read_all)
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 var s: String
 while not f.eof do
     s = f.read_line
@@ -166,7 +166,7 @@ printn(f.read_all)
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 var s: String
 while not f.eof do
     s = f.read_line
diff --git a/tests/sav/test_parser_args1.res b/tests/sav/test_parser_args1.res
index d5ff252..debcdd3 100644
--- a/tests/sav/test_parser_args1.res
+++ b/tests/sav/test_parser_args1.res
@@ -774,22 +774,22 @@ Start ../src/test_parser.nit:17,1--147,1
                                 AListExprs ../src/test_parser.nit:116,44
                               TCpar ")" ../src/test_parser.nit:116,45
                       ABlockExpr ../src/test_parser.nit:118,4--121,5
-                        AVardeclExpr ../src/test_parser.nit:118,4--31
+                        AVardeclExpr ../src/test_parser.nit:118,4--33
                           TKwvar "var" ../src/test_parser.nit:118,4--6
                           TId "f" ../src/test_parser.nit:118,8
                           TAssign "=" ../src/test_parser.nit:118,10
-                          ANewExpr ../src/test_parser.nit:118,12--31
+                          ANewExpr ../src/test_parser.nit:118,12--33
                             TKwnew "new" ../src/test_parser.nit:118,12--14
-                            AType ../src/test_parser.nit:118,16--23
-                              TClassid "IFStream" ../src/test_parser.nit:118,16--23
-                            TId "open" ../src/test_parser.nit:118,25--28
-                            AParExprs ../src/test_parser.nit:118,29--31
-                              TOpar "(" ../src/test_parser.nit:118,29
-                              ACallExpr ../src/test_parser.nit:118,30
-                                AImplicitSelfExpr ../src/test_parser.nit:118,30
-                                TId "a" ../src/test_parser.nit:118,30
-                                AListExprs ../src/test_parser.nit:118,30
-                              TCpar ")" ../src/test_parser.nit:118,31
+                            AType ../src/test_parser.nit:118,16--25
+                              TClassid "FileReader" ../src/test_parser.nit:118,16--25
+                            TId "open" ../src/test_parser.nit:118,27--30
+                            AParExprs ../src/test_parser.nit:118,31--33
+                              TOpar "(" ../src/test_parser.nit:118,31
+                              ACallExpr ../src/test_parser.nit:118,32
+                                AImplicitSelfExpr ../src/test_parser.nit:118,32
+                                TId "a" ../src/test_parser.nit:118,32
+                                AListExprs ../src/test_parser.nit:118,32
+                              TCpar ")" ../src/test_parser.nit:118,33
                         ACallAssignExpr ../src/test_parser.nit:119,4--32
                           AImplicitSelfExpr ../src/test_parser.nit:119,4
                           TId "source" ../src/test_parser.nit:119,4--9
diff --git a/tests/sav/test_parser_args2.res b/tests/sav/test_parser_args2.res
index 36dd49b..32c94e3 100644
--- a/tests/sav/test_parser_args2.res
+++ b/tests/sav/test_parser_args2.res
@@ -641,13 +641,13 @@ Read token at ../src/test_parser.nit:118,4--6 text='var'
 Read token at ../src/test_parser.nit:118,8 text='f'
 Read token at ../src/test_parser.nit:118,10 text='='
 Read token at ../src/test_parser.nit:118,12--14 text='new'
-Read token at ../src/test_parser.nit:118,16--23 text='IFStream'
-Read token at ../src/test_parser.nit:118,24 text='.'
-Read token at ../src/test_parser.nit:118,25--28 text='open'
-Read token at ../src/test_parser.nit:118,29 text='('
-Read token at ../src/test_parser.nit:118,30 text='a'
-Read token at ../src/test_parser.nit:118,31 text=')'
-Read token at ../src/test_parser.nit:118,32--119,0 text='
+Read token at ../src/test_parser.nit:118,16--25 text='FileReader'
+Read token at ../src/test_parser.nit:118,26 text='.'
+Read token at ../src/test_parser.nit:118,27--30 text='open'
+Read token at ../src/test_parser.nit:118,31 text='('
+Read token at ../src/test_parser.nit:118,32 text='a'
+Read token at ../src/test_parser.nit:118,33 text=')'
+Read token at ../src/test_parser.nit:118,34--119,0 text='
 '
 Read token at ../src/test_parser.nit:119,4--9 text='source'
 Read token at ../src/test_parser.nit:119,11 text='='
diff --git a/tests/test_deserialization.nit b/tests/test_deserialization.nit
index 8d11236..deb07b7 100644
--- a/tests/test_deserialization.nit
+++ b/tests/test_deserialization.nit
@@ -124,7 +124,7 @@ var tests = new Array[Serializable].with_items(a, b, c, d, e, fi, ff)
 #alt1# tests = new Array[Serializable].with_items(a, b, c, d)
 
 for o in tests do
-	var stream = new StringOStream
+	var stream = new StringWriter
 	var serializer = new JsonSerializer(stream)
 	serializer.serialize(o)
 
diff --git a/tests/test_directory_create.nit b/tests/test_directory_create.nit
index f64fed1..950e113 100644
--- a/tests/test_directory_create.nit
+++ b/tests/test_directory_create.nit
@@ -15,9 +15,9 @@
 # limitations under the License.
 
 "out/test_directory_create.write/tmp_dir".mkdir
-var f =  new OFStream.open("out/test_directory_create.write/tmp_file")
+var f =  new FileWriter.open("out/test_directory_create.write/tmp_file")
 f.write("test")
 f.close
-f =  new OFStream.open("out/test_directory_create.write/tmp_dir/tmp_file_2")
+f =  new FileWriter.open("out/test_directory_create.write/tmp_dir/tmp_file_2")
 f.write("other test")
 f.close
diff --git a/tests/test_exec.nit b/tests/test_exec.nit
index da3bf84..efb94b7 100644
--- a/tests/test_exec.nit
+++ b/tests/test_exec.nit
@@ -22,14 +22,14 @@ print hw.status
 
 print ""
 
-var ip = new IProcess("echo", "B hello world!")
+var ip = new ProcessReader("echo", "B hello world!")
 ip.read_line.output
 ip.wait
 print ip.status
 
 print ""
 
-var op = new OProcess.from_a("cat", null)
+var op = new ProcessWriter.from_a("cat", null)
 op.write("C hello world!\n")
 op.close
 op.wait
@@ -37,7 +37,7 @@ print op.status
 
 print ""
 
-var iop = new IOProcess.from_a("cat", null)
+var iop = new ProcessDuplex.from_a("cat", null)
 iop.write("D hello world!\n")
 iop.read_line.output
 iop.close
@@ -52,7 +52,7 @@ print e1.status
 
 print ""
 
-var ioperr = new IOProcess.from_a("bad command", null)
+var ioperr = new ProcessDuplex.from_a("bad command", null)
 ioperr.write("D hello world!\n")
 ioperr.read_line.output
 ioperr.close
diff --git a/tests/test_fdstream.nit b/tests/test_fdstream.nit
index 6de686a..0754f10 100644
--- a/tests/test_fdstream.nit
+++ b/tests/test_fdstream.nit
@@ -16,9 +16,9 @@
 
 import file
 
-var fd_in = new IFStream.from_fd(0)
-var fd_out = new OFStream.from_fd(1)
-var fd_err = new OFStream.from_fd(2)
+var fd_in = new FileReader.from_fd(0)
+var fd_out = new FileWriter.from_fd(1)
+var fd_err = new FileWriter.from_fd(2)
 
 fd_out.write("Hello\n")
 
diff --git a/tests/test_file_copy.nit b/tests/test_file_copy.nit
index 632da3c..0d8a256 100644
--- a/tests/test_file_copy.nit
+++ b/tests/test_file_copy.nit
@@ -21,6 +21,6 @@ var src = "test_file_copy.nit"
 var dst = "{dir}/copy.nit"
 src.file_copy_to dst
 
-var file = new IFStream.open(dst)
+var file = new FileReader.open(dst)
 printn file.read_all
 file.close
diff --git a/tests/test_file_open_fail.nit b/tests/test_file_open_fail.nit
index f71ed82..8e932d3 100644
--- a/tests/test_file_open_fail.nit
+++ b/tests/test_file_open_fail.nit
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var ifs = new IFStream.open("donotcreate.bing")
+var ifs = new FileReader.open("donotcreate.bing")
 
 var s = ifs.read_all
 
diff --git a/tests/test_file_read.nit b/tests/test_file_read.nit
index 453a844..cffc2d2 100644
--- a/tests/test_file_read.nit
+++ b/tests/test_file_read.nit
@@ -14,7 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 var s: String
 while not f.eof do
     s = f.read_line
diff --git a/tests/test_file_read2.nit b/tests/test_file_read2.nit
index bc2943b..f4778b1 100644
--- a/tests/test_file_read2.nit
+++ b/tests/test_file_read2.nit
@@ -12,17 +12,17 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new IFStream.open("test_file_read.nit")
+var f = new FileReader.open("test_file_read.nit")
 print f.read_all
 
 print "---"
 
-f = new IFStream.open("test_file_read.nit")
+f = new FileReader.open("test_file_read.nit")
 print f.read_lines.join("\n")
 
 print "---"
 
-f = new IFStream.open("test_file_read.nit")
+f = new FileReader.open("test_file_read.nit")
 print f.each_line.to_a.join("\n")
 
 print "---"
diff --git a/tests/test_file_write.nit b/tests/test_file_write.nit
index 5a8f936..d6f02b1 100644
--- a/tests/test_file_write.nit
+++ b/tests/test_file_write.nit
@@ -14,7 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-var f = new OFStream.open("out/test_file_write.write")
+var f = new FileWriter.open("out/test_file_write.write")
    f.write("Quatre vingt et un : {421}\n")
    f.write("Une autre ligne\nencore un")
    f.write(['e', '\n'].to_s)
diff --git a/tests/test_filterstream.nit b/tests/test_filterstream.nit
index 59a449d..3a2c85a 100644
--- a/tests/test_filterstream.nit
+++ b/tests/test_filterstream.nit
@@ -20,16 +20,16 @@ import filter_stream
 var filename_1 = "out/test_filterstream_tmp1.write"
 var filename_2 = "out/test_filterstream_tmp2.write"
 
-var output_file_1 = new OFStream.open(filename_1)
-var output_file_2 = new OFStream.open(filename_2)
+var output_file_1 = new FileWriter.open(filename_1)
+var output_file_2 = new FileWriter.open(filename_2)
 
 var stream_demux = new StreamDemux(output_file_1, output_file_2)
 
 stream_demux.write("Hello World !!\n")
 stream_demux.close
 
-var input_file_1 = new IFStream.open(filename_1)
-var input_file_2 = new IFStream.open(filename_2)
+var input_file_1 = new FileReader.open(filename_1)
+var input_file_2 = new FileReader.open(filename_2)
 
 var stream_cat = new StreamCat(input_file_1,input_file_2)
 
diff --git a/tests/test_for_abuse.nit b/tests/test_for_abuse.nit
index cae1cd1..9400641 100644
--- a/tests/test_for_abuse.nit
+++ b/tests/test_for_abuse.nit
@@ -14,7 +14,7 @@
 
 import for_abuse
 
-var escape_f: nullable IStream = null
+var escape_f: nullable Reader = null
 for f in file_open("test_for_abuse.nit") do
 	escape_f = f
 	print f.read_line
diff --git a/tests/test_serialization.nit b/tests/test_serialization.nit
index 59aac77..1d3de0a 100644
--- a/tests/test_serialization.nit
+++ b/tests/test_serialization.nit
@@ -95,7 +95,7 @@ var d = new D(false, 'b', 123.123, 2345, "new line ->\n<-", null, 1111, "\t\f\"\
 d.d = d
 
 for o in new Array[Serializable].with_items(a, b, c, d) do
-	var stream = new StringOStream
+	var stream = new StringWriter
 	var serializer = new JsonSerializer(stream)
 	serializer.serialize(o)
 
diff --git a/tests/test_stream_poll.nit b/tests/test_stream_poll.nit
index 7981d06..3d5094c 100644
--- a/tests/test_stream_poll.nit
+++ b/tests/test_stream_poll.nit
@@ -21,11 +21,11 @@ var p1
 var p2
 var p3
 
-p1 = new IProcess( "sleep", "0.2" )
-p2 = new IProcess( "sleep", "0.1" )
-p3 = new IProcess( "sleep", "0.4" )
+p1 = new ProcessReader( "sleep", "0.2" )
+p2 = new ProcessReader( "sleep", "0.1" )
+p3 = new ProcessReader( "sleep", "0.4" )
 
-var order = new Array[FStream]
+var order = new Array[FileStream]
 var streams = [p1.stream_in, p2.stream_in, p3.stream_in]
 
 while not streams.is_empty do
@@ -33,7 +33,7 @@ while not streams.is_empty do
 	if s == null then continue # may have been interrupted
 
 	order.add( s )
-	streams.remove( s.as(IFStream ) )
+	streams.remove( s.as(FileReader ) )
 end
 
 print order[0] == p2.stream_in