doc (WIP)

lib/scope.js

@@ -1,5 +1,12 @@
 AST_Scope.DEFMETHOD("figure_out_scope", function(){
-    // step 1: handle definitions
+    // This does what ast_add_scope did in UglifyJS v1.
+    //
+    // Part of it could be done at parse time, but it would complicate
+    // the parser (and it's already kinda complex).  It's also worth
+    // having it separated because we might need to call it multiple
+    // times on the same tree.
+
+    // pass 1: setup scope chaining and handle definitions
     var scope = null;
     var tw = new TreeWalker(function(node, descend){
         if (node instanceof AST_Scope) {
@@ -41,7 +48,8 @@ AST_Scope.DEFMETHOD("figure_out_scope", function(){
         }
     });
     this.walk(tw);
-    // step 2: find back references and eval/with
+
+    // pass 2: find back references and eval/with
     var tw = new TreeWalker(function(node){
         if (node instanceof AST_LabelRef) {
             var sym = node.scope.find_label(node);
@@ -62,26 +70,31 @@ AST_Scope.DEFMETHOD("figure_out_scope", function(){
     });
     this.walk(tw);
 });
+
 AST_Scope.DEFMETHOD("find_variable", function(name){
     if (name instanceof AST_Symbol) name = name.name;
     return this.variables[name] ||
         (this.name && this.name.name == name && this.name) ||
         (this.parent_scope && this.parent_scope.find_variable(name));
 });
+
 AST_Scope.DEFMETHOD("find_label", function(name){
     if (name instanceof AST_Symbol) name = name.name;
     return this.labels[name];
 });
+
 AST_Scope.DEFMETHOD("def_function", function(symbol){
     this.def_variable(symbol);
     this.functions[symbol.name] = symbol;
     symbol.scope = this;
 });
+
 AST_Scope.DEFMETHOD("def_variable", function(symbol){
     this.variables[symbol.name] = symbol;
     delete this.functions[symbol.name];
     symbol.scope = this;
 });
+
 AST_Scope.DEFMETHOD("def_label", function(symbol){
     this.labels[symbol.name] = symbol;
     symbol.scope = this;