passing through values with line number information that look and act like Ruby natives

lib/coffee-script.rb

@@ -1,4 +1,6 @@
 $LOAD_PATH.unshift(File.dirname(__FILE__))
+require "coffee_script/value"
+require "coffee_script/scope"
 require "coffee_script/lexer"
 require "coffee_script/parser"
 require "coffee_script/nodes"

lib/coffee_script/lexer.rb

@@ -123,7 +123,7 @@ class Lexer
   end
 
   def token(tag, value)
-    @tokens << [tag, value]
+    @tokens << [tag, Value.new(value, @line)]
   end
 
   def last_value

lib/coffee_script/nodes.rb

@@ -1,36 +1,3 @@
-class Scope
-
-  attr_reader :parent, :temp_variable
-
-  def initialize(parent=nil)
-    @parent = parent
-    @variables = {}
-    @temp_variable = @parent ? @parent.temp_variable : 'a'
-  end
-
-  # Look up a variable in lexical scope, or declare it if not found.
-  def find(name, remote=false)
-    found = check(name, remote)
-    return found if found || remote
-    @variables[name] = true
-    found
-  end
-
-  # Just check for the pre-definition of a variable.
-  def check(name, remote=false)
-    return true if @variables[name]
-    @parent && @parent.find(name, true)
-  end
-
-  # Find an available, short variable name.
-  def free_variable
-    @temp_variable.succ! while check(@temp_variable)
-    @variables[@temp_variable] = true
-    @temp_variable.dup
-  end
-
-end
-
 class Node
   # Tabs are two spaces for pretty-printing.
   TAB = '  '

lib/coffee_script/scope.rb

@@ -0,0 +1,33 @@
+# A class to handle lookups for lexically scoped variables.
+class Scope
+
+  attr_reader :parent, :temp_variable
+
+  def initialize(parent=nil)
+    @parent = parent
+    @variables = {}
+    @temp_variable = @parent ? @parent.temp_variable : 'a'
+  end
+
+  # Look up a variable in lexical scope, or declare it if not found.
+  def find(name, remote=false)
+    found = check(name, remote)
+    return found if found || remote
+    @variables[name] = true
+    found
+  end
+
+  # Just check for the pre-definition of a variable.
+  def check(name, remote=false)
+    return true if @variables[name]
+    @parent && @parent.find(name, true)
+  end
+
+  # Find an available, short variable name.
+  def free_variable
+    @temp_variable.succ! while check(@temp_variable)
+    @variables[@temp_variable] = true
+    @temp_variable.dup
+  end
+
+end

lib/coffee_script/value.rb

@@ -0,0 +1,34 @@
+# Instead of producing raw Ruby objects, the Lexer produces values of this
+# class, tagged with line number information.
+class Value
+  attr_reader :line
+
+  def initialize(value, line)
+    @value, @line = value, line
+  end
+
+  def to_str
+    @value.to_s
+  end
+  alias_method :to_s, :to_str
+
+  def inspect
+    @value.inspect
+  end
+
+  def ==(other)
+    @value == other
+  end
+
+  def [](index)
+    @value[index]
+  end
+
+  def eql?(other)
+    @value.eql?(other)
+  end
+
+  def hash
+    @value.hash
+  end
+end