merging jeff olson's work

lib/coffee_script/scope.js

@@ -0,0 +1,73 @@
+(function(){
+  var dup;
+  var __hasProp = Object.prototype.hasOwnProperty;
+  dup = function dup(input) {
+    var __a, __b, __c, key, output, val;
+    output = null;
+    if (input instanceof Array) {
+      output = [];
+      __a = input;
+      for (__b = 0; __b < __a.length; __b++) {
+        val = __a[__b];
+        output.push(val);
+      }
+    } else {
+      output = {
+      };
+      __c = input;
+      for (key in __c) {
+        val = __c[key];
+        if (__hasProp.call(__c, key)) {
+          output.key = val;
+        }
+      }
+      output;
+    }
+    return output;
+  };
+  // scope objects form a tree corresponding to the shape of the function
+  // definitions present in the script. They provide lexical scope, to determine
+  // whether a variable has been seen before or if it needs to be declared.
+  exports.Scope = function Scope(parent, expressions, func) {
+    var __a;
+    // Initialize a scope with its parent, for lookups up the chain,
+    // as well as the Expressions body where it should declare its variables,
+    // and the function that it wraps.
+    this.parent = parent;
+    this.expressions = expressions;
+    this.function = func;
+    this.variables = {
+    };
+    __a = this.temp_variable = this.parent ? dup(this.parent.temp_variable) : '__a';
+    return Scope === this.constructor ? this : __a;
+  };
+  // Look up a variable in lexical scope, or declare it if not found.
+  exports.Scope.prototype.find = function find(name, rem) {
+    var found, remote;
+    remote = (typeof rem !== "undefined" && rem !== null) ? rem : false;
+    found = this.check(name);
+    if (found || remote) {
+      return found;
+    }
+    this.variables[name] = 'var';
+    return found;
+  };
+  // Define a local variable as originating from a parameter in current scope
+  // -- no var required.
+  exports.Scope.prototype.parameter = function parameter(name) {
+    return this.variables[name] = 'param';
+  };
+  // Just check to see if a variable has already been declared.
+  exports.Scope.prototype.check = function check(name) {
+    if ((typeof this.variables[name] !== "undefined" && this.variables[name] !== null)) {
+      return true;
+    }
+    // TODO: what does that ruby !! mean..? need to follow up
+    // .. this next line is prolly wrong ..
+    return !!(this.parent && this.parent.check(name));
+  };
+  // You can reset a found variable on the immediate scope.
+  exports.Scope.prototype.reset = function reset(name) {
+    return this.variables[name] = undefined;
+  };
+})();