},
parent: function(n) {
return this.stack[this.stack.length - 2 - (n || 0)];
- }
+ },
+ push: function (node) {
+ this.stack.push(node);
+ },
+ pop: function() {
+ return this.stack.pop();
+ },
+ self: function() {
+ return this.stack[this.stack.length - 1];
+ },
+ find_parent: function(type) {
+ var stack = this.stack;
+ for (var i = stack.length; --i >= 0;) {
+ var x = stack[i];
+ if (x instanceof type) return x;
+ }
+ },
+ in_boolean_context: function() {
+ var stack = this.stack;
+ var i = stack.length, self = stack[--i];
+ while (i > 0) {
+ var p = stack[--i];
+ if ((p instanceof AST_If && p.condition === self) ||
+ (p instanceof AST_Conditional && p.condition === self) ||
+ (p instanceof AST_DWLoop && p.condition === self) ||
+ (p instanceof AST_For && p.condition === self) ||
+ (p instanceof AST_UnaryPrefix && p.operator == "!" && p.expression === self))
+ {
+ return true;
+ }
+ if (!(p instanceof AST_Binary && (p.operator == "&&" || p.operator == "||")))
+ return false;
+ self = p;
+ }
+ },
};
// squeezing nodes.
function Compressor(options, false_by_default) {
- options = defaults(options, {
+ if (!(this instanceof Compressor))
+ return new Compressor(options, false_by_default);
+ TreeTransformer.call(this, this.before, this.after);
+ this.options = defaults(options, {
sequences : !false_by_default,
properties : !false_by_default,
dead_code : !false_by_default,
warnings : true
});
- var stack = [];
- function in_boolean_context() {
- var i = stack.length, self = stack[--i];
- while (i > 0) {
- var p = stack[--i];
- if ((p instanceof AST_If && p.condition === self) ||
- (p instanceof AST_Conditional && p.condition === self) ||
- (p instanceof AST_DWLoop && p.condition === self) ||
- (p instanceof AST_For && p.condition === self) ||
- (p instanceof AST_UnaryPrefix && p.operator == "!" && p.expression === self))
- {
- return true;
- }
- if (!(p instanceof AST_Binary && (p.operator == "&&" || p.operator == "||")))
- return false;
- self = p;
- }
- };
- function find_parent(type) {
- for (var i = stack.length; --i >= 0;) {
- var x = stack[i];
- if (x instanceof type) return x;
- }
- };
- return {
- option : function(key) { return options[key] },
- push_node : function(node) { stack.push(node) },
- pop_node : function() { return stack.pop() },
- stack : function() { return stack },
- self : function() { return stack[stack.length - 1] },
- parent : function(n) {
- return stack[stack.length - 2 - (n || 0)];
- },
- warn : function() {
- if (options.warnings)
- AST_Node.warn.apply(AST_Node, arguments);
- },
- in_boolean_context: in_boolean_context,
- find_parent: find_parent,
- };
};
+Compressor.prototype = new TreeTransformer;
+defaults(Compressor.prototype, {
+ option: function(key) { return this.options[key] },
+ warn: function() {
+ if (this.options.warnings)
+ AST_Node.warn.apply(AST_Node, arguments);
+ }
+});
+
(function(undefined){
AST_Node.DEFMETHOD("optimize", function(){
function SQUEEZE(nodetype, squeeze) {
nodetype.DEFMETHOD("squeeze", function(compressor){
- compressor.push_node(this);
+ compressor.push(this);
var self = this.clone(), opt;
opt = squeeze(self, compressor);
if (opt !== undefined) self = opt;
opt = self.optimize(compressor);
if (opt !== undefined) self = opt;
- compressor.pop_node();
+ compressor.pop();
return self;
});
};
self.expression = self.expression.squeeze(compressor);
});
- SQUEEZE(AST_UnaryPrefix, function(self, compressor){
- self.expression = self.expression.squeeze(compressor);
- });
-
SQUEEZE(AST_Binary, function(self, compressor){
self.left = self.left.squeeze(compressor);
self.right = self.right.squeeze(compressor);