lib: intro `prompt`, basic Apache 2.0 service to display a prompt

[nit.git] / contrib / nitin / nitin.nit

diff --git a/contrib/nitin/nitin.nit b/contrib/nitin/nitin.nit
index ae2c030..2497411 100644 (file)
--- a/contrib/nitin/nitin.nit
+++ b/contrib/nitin/nitin.nit
@@ -22,6 +22,7 @@ module nitin
 import nitc::interpreter
 import nitc::frontend
 import nitc::parser_util
+intrude import nitc::scope
 
 redef class ToolContext
 
@@ -42,6 +43,7 @@ redef class ToolContext
        fun p_module(string: String): ANode
        do
                var source_name = opt_source_name.value or else ""
+               string = "\n" * last_line + string
                var source = new SourceFile.from_string(source_name, string)
                var lexer = new Lexer(source)
                var parser = new Parser(lexer)
@@ -69,6 +71,9 @@ redef class ToolContext
        # With the default implementation, the history is dropped
        fun readline_add_history(text: String) do end
 
+       # The last line number read by `i_parse`
+       var last_line = 0
+
        # Parse the input of the user as a module
        fun i_parse(prompt: String): nullable ANode
        do
@@ -83,7 +88,14 @@ redef class ToolContext
                                s = readline(prompt)
                        end
                        if s == null then return null
-                       if s == "" then continue
+                       if s == "" then
+                               if oldtext != "" then
+                                       oldtext += "\n"
+                               else
+                                       last_line += 1
+                               end
+                               continue
+                       end
 
                        if s.chars.first == ':' then
                                var res = new TString
@@ -95,19 +107,76 @@ redef class ToolContext
                        oldtext = ""
                        var n = p_module(text)
 
-                       if n isa AParserError and (n.token isa EOF) then
+                       if n isa AParserError and (n.token isa EOF or n.token isa TBadTString or n.token isa TBadExtern) then
                                # Unexpected end of file, thus continuing
                                if oldtext == "" then prompt = "." * prompt.length
                                oldtext = text
                                continue
                        end
 
+                       last_line = n.location.file.line_starts.length - 1
                        readline_add_history(text.chomp)
                        return n
                end
        end
 end
 
+redef class AMethPropdef
+       var injected_variables: nullable Map[Variable, Instance] = null is writable
+       var new_variables: nullable Array[Variable] = null
+
+       redef fun accept_scope_visitor(v)
+       do
+               var injected_variables = self.injected_variables
+               if injected_variables == null then
+                       super
+                       return
+               end
+
+               # Inject main variables in the initial scope
+               var scope = v.scopes.first
+               for variable in injected_variables.keys do
+                       scope.variables[variable.name] = variable
+               end
+
+               super
+
+               # Gather new top-level variables as main variables
+               scope = v.scopes.first
+               var new_variables = new Array[Variable]
+               for variable in scope.variables.values do
+                       if not injected_variables.has_key(variable) then
+                               new_variables.add(variable)
+                       end
+               end
+               self.new_variables = new_variables
+       end
+
+       redef fun call_commons(v, m, a, f)
+       do
+               var injected_variables = self.injected_variables
+               if injected_variables == null then return super
+
+               # Inject main variables in the frame
+               assert f isa InterpreterFrame
+               for variable, i in injected_variables do
+                       f.map[variable] = i
+               end
+
+               var res = super
+
+               # Update the values of the variables
+               for variable in injected_variables.keys do
+                       injected_variables[variable] = f.map[variable]
+               end
+               # Retrieve the values of the new main variables
+               for variable in new_variables.as(not null) do
+                       injected_variables[variable] = f.map[variable]
+               end
+
+               return res
+       end
+end
 
 # Create a tool context to handle options and paths
 var toolcontext = new ToolContext
@@ -143,6 +212,8 @@ var sys_type = mainobj.mtype.as(MClassType)
 var mainprop = mainmodule.try_get_primitive_method("main", sys_type.mclass)
 assert mainprop != null
 
+var main_variables = new Map[Variable, Instance]
+
 var l = 0
 loop
        # Next piece of Nit code
@@ -164,7 +235,8 @@ loop
 
        # An error
        if n isa AError then
-               print "{n.location.colored_line("0;31")}: {n.message}"
+               modelbuilder.error(n, n.message)
+               toolcontext.check_errors
                continue
        end
 
@@ -177,6 +249,14 @@ loop
        l += 1
        var newmodule = modelbuilder.load_rt_module(mainmodule, amodule, "input-{l}")
        if newmodule == null then continue
+
+       var main_method = null
+       if amodule.n_classdefs.not_empty and amodule.n_classdefs.last isa AMainClassdef then
+               main_method = amodule.n_classdefs.last.n_propdefs.first
+               assert main_method isa AMethPropdef
+               main_method.injected_variables = main_variables
+       end
+
        modelbuilder.run_phases
        if not toolcontext.check_errors then
                toolcontext.error_count = 0
@@ -187,7 +267,7 @@ loop
        interpreter.mainmodule = mainmodule
 
        # Run the main if the AST contains a main
-       if amodule.n_classdefs.not_empty and amodule.n_classdefs.last isa AMainClassdef then
+       if main_method != null then
                do
                        interpreter.catch_count += 1
                        interpreter.send(mainprop, [mainobj])