Self-compiler: now does while loops

lib/coffee_script/lexer.js

@@ -314,10 +314,10 @@
     num = 0;
     pos = string.indexOf(letter);
     while (pos !== -1) {
-      count += 1;
+      num += 1;
       pos = string.indexOf(letter, pos + 1);
     }
-    return count;
+    return num;
   };
   // Attempt to match a string against the current chunk, returning the indexed
   // match.

lib/coffee_script/nodes.js

@@ -1,5 +1,5 @@
 (function(){
-  var AccessorNode, ArrayNode, AssignNode, CallNode, ClosureNode, CodeNode, CommentNode, Expressions, ExtendsNode, IndexNode, LiteralNode, Node, ObjectNode, PushNode, RangeNode, ReturnNode, SliceNode, SplatNode, TAB, TRAILING_WHITESPACE, ThisNode, ValueNode, any, compact, del, dup, flatten, inherit, merge, statement;
+  var AccessorNode, ArrayNode, AssignNode, CallNode, ClosureNode, CodeNode, CommentNode, Expressions, ExtendsNode, IndexNode, LiteralNode, Node, ObjectNode, PushNode, RangeNode, ReturnNode, SliceNode, SplatNode, TAB, TRAILING_WHITESPACE, ThisNode, ValueNode, WhileNode, any, compact, del, dup, flatten, inherit, merge, statement;
   var __hasProp = Object.prototype.hasOwnProperty;
   process.mixin(require('./scope'));
   // The abstract base class for all CoffeeScript nodes.
@@ -372,7 +372,7 @@
     compile: function compile(o) {
       o = o || {
       };
-      return o.scope ? compile.__superClass__.constructor.call(this, o) : this.compile_root(o);
+      return o.scope ? Node.prototype.compile.call(this, o) : this.compile_root(o);
     },
     // Compile each expression in the Expressions body.
     compile_node: function compile_node(o) {
@@ -998,4 +998,36 @@
       return "Array.prototype.slice.call(" + this.name + ', ' + this.index + ')';
     }
   }));
+  // A while loop, the only sort of low-level loop exposed by CoffeeScript. From
+  // it, all other loops can be manufactured.
+  WhileNode = (exports.WhileNode = inherit(Node, {
+    constructor: function constructor(condition, body) {
+      this.children = [(this.condition = condition), (this.body = body)];
+      return this;
+    },
+    top_sensitive: function top_sensitive() {
+      return true;
+    },
+    compile_node: function compile_node(o) {
+      var cond, post, pre, returns, rvar, set, top;
+      returns = del(o, 'returns');
+      top = del(o, 'top') && !returns;
+      o.indent = this.idt(1);
+      o.top = true;
+      cond = this.condition.compile(o);
+      set = '';
+      if (!top) {
+        rvar = o.scope.free_variable();
+        set = this.idt() + rvar + ' = [];\n';
+        this.body = PushNode.wrap(rvar, this.body);
+      }
+      post = returns ? '\n' + this.idt() + 'return ' + rvar + ';' : '';
+      pre = set + this.idt() + 'while (' + cond + ')';
+      if (!this.body) {
+        return pre + ' null;' + post;
+      }
+      return pre + ' {\n' + this.body.compile(o) + '\n' + this.idt() + '}' + post;
+    }
+  }));
+  statement(WhileNode);
 })();

src/lexer.coffee

@@ -246,9 +246,9 @@ lex::count: (string, letter) ->
   num: 0
   pos: string.indexOf(letter)
   while pos isnt -1
-    count += 1
+    num += 1
     pos: string.indexOf(letter, pos + 1)
-  count
+  num
 
 # Attempt to match a string against the current chunk, returning the indexed
 # match.

src/nodes.coffee

@@ -182,7 +182,7 @@ Expressions: exports.Expressions: inherit Node, {
 
   compile: (o) ->
     o ||= {}
-    if o.scope then super(o) else @compile_root(o)
+    if o.scope then Node::compile.call(this, o) else @compile_root(o)
 
   # Compile each expression in the Expressions body.
   compile_node: (o) ->
@@ -711,6 +711,37 @@ SplatNode: exports.SplatNode: inherit Node, {
 
 }
 
+# A while loop, the only sort of low-level loop exposed by CoffeeScript. From
+# it, all other loops can be manufactured.
+WhileNode: exports.WhileNode: inherit Node, {
+
+  constructor: (condition, body) ->
+    @children:[@condition: condition, @body: body]
+    this
+
+  top_sensitive: ->
+    true
+
+  compile_node: (o) ->
+    returns:    del(o, 'returns')
+    top:        del(o, 'top') and not returns
+    o.indent:   @idt(1)
+    o.top:      true
+    cond:       @condition.compile(o)
+    set:        ''
+    if not top
+      rvar:     o.scope.free_variable()
+      set:      @idt() + rvar + ' = [];\n'
+      @body:    PushNode.wrap(rvar, @body)
+    post:       if returns then '\n' + @idt() + 'return ' + rvar + ';' else ''
+    pre:        set + @idt() + 'while (' + cond + ')'
+    return pre + ' null;' + post if not @body
+    pre + ' {\n' + @body.compile(o) + '\n' + @idt() + '}' + post
+
+}
+
+statement WhileNode
+