X-Git-Url: http://nitlanguage.org?ds=sidebyside

diff --git a/lib/standard/stream.nit b/lib/standard/stream.nit
index d26d95f..a94601c 100644
--- a/lib/standard/stream.nit
+++ b/lib/standard/stream.nit
@@ -13,13 +13,14 @@
 # Input and output streams of characters
 module stream
 
-import string
+intrude import ropes
 
 in "C" `{
 	#include <unistd.h>
 	#include <poll.h>
 	#include <errno.h>
 	#include <string.h>
+	#include <signal.h>
 `}
 
 # Abstract stream class
@@ -88,16 +89,77 @@ interface IStream
 	fun eof: Bool is abstract
 end
 
+# IStream capable of declaring if readable without blocking
+interface PollableIStream
+	super IStream
+
+	# Is there something to read? (without blocking)
+	fun poll_in: Bool is abstract
+
+end
+
 # Abstract output stream
 interface OStream
 	super IOS
 	# write a string
-	fun write(s: String) is abstract
+	fun write(s: Text) is abstract
 
 	# Can the stream be used to write
 	fun is_writable: Bool is abstract
 end
 
+# Things that can be efficienlty writen to a OStream
+#
+# 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
+#
+# ready-to-save documents usually provide this interface.
+interface Streamable
+	# Write itself to a `stream`
+	# The specific logic it let to the concrete subclasses
+	fun write_to(stream: OStream) is abstract
+
+	# Like `write_to` but return a new String (may be quite large)
+	#
+	# This funtionnality is anectodical, since the point
+	# of streamable object to to be efficienlty written to a
+	# stream without having to allocate and concatenate strings
+	fun write_to_string: String
+	do
+		var stream = new StringOStream
+		write_to(stream)
+		return stream.to_s
+	end
+end
+
+redef class Text
+	super Streamable
+	redef fun write_to(stream) do stream.write(self)
+end
+
+redef class RopeNode
+	super Streamable
+end
+
+redef class Leaf
+
+	redef fun write_to(s) do s.write(str)
+end
+
+redef class Concat
+
+	redef fun write_to(s)
+	do
+		if left != null then left.write_to(s)
+		if right != null then right.write_to(s)
+	end
+end
+
+redef class RopeString
+
+	redef fun write_to(s) do root.write_to(s)
+end
+
 # Input streams with a buffer
 abstract class BufferedIStream
 	super IStream
@@ -117,24 +179,20 @@ abstract class BufferedIStream
 
 	redef fun read(i)
 	do
-		var s = new FlatBuffer.with_capacity(i)
-		var j = _buffer_pos
-		var k = _buffer.length
-		while i > 0 do
-			if j >= k then
+		if _buffer.length == _buffer_pos then
+			if not eof then
 				fill_buffer
-				if eof then return s.to_s
-				j = _buffer_pos
-				k = _buffer.length
-			end
-			while j < k and i > 0 do
-				s.add(_buffer.chars[j])
-				j +=  1
-				i -= 1
+				return read(i)
 			end
+			return ""
 		end
-		_buffer_pos = j
-		return s.to_s
+		if _buffer_pos + i >= _buffer.length then
+			var from = _buffer_pos
+			_buffer_pos = _buffer.length
+			return _buffer.substring_from(from).to_s
+		end
+		_buffer_pos += i
+		return _buffer.substring(_buffer_pos - i, i).to_s
 	end
 
 	redef fun read_all
@@ -361,6 +419,13 @@ class StringOStream
 
 	private var content = new Array[String]
 	redef fun to_s do return content.to_s
-	redef fun is_writable do return true
-	redef fun write(str) do content.add(str)
+	redef fun is_writable do return not closed
+	redef fun write(str)
+	do
+		assert not closed
+		content.add(str.to_s)
+	end
+
+	protected var closed = false
+	redef fun close do closed = true
 end