return self;
});
- function has_side_effects_or_prop_access(node, compressor) {
- var save_pure_getters = compressor.option("pure_getters");
- compressor.options.pure_getters = false;
- var ret = node.has_side_effects(compressor);
- compressor.options.pure_getters = save_pure_getters;
- return ret;
- }
-
AST_Binary.DEFMETHOD("lift_sequences", function(compressor){
if (compressor.option("sequences")) {
if (this.left instanceof AST_Seq) {
var x = seq.to_array();
this.left = x.pop();
x.push(this);
- seq = AST_Seq.from_array(x).transform(compressor);
- return seq;
- }
- if (this.right instanceof AST_Seq
- && this instanceof AST_Assign
- && !has_side_effects_or_prop_access(this.left, compressor)) {
- var seq = this.right;
- var x = seq.to_array();
- this.right = x.pop();
- x.push(this);
- seq = AST_Seq.from_array(x).transform(compressor);
- return seq;
+ return AST_Seq.from_array(x).optimize(compressor);
+ }
+ if (this.right instanceof AST_Seq && !this.left.has_side_effects(compressor)) {
+ var assign = this.operator == "=" && this.left instanceof AST_SymbolRef;
+ var root = this.right;
+ var cursor, seq = root;
+ while (assign || !seq.car.has_side_effects(compressor)) {
+ cursor = seq;
+ if (seq.cdr instanceof AST_Seq) {
+ seq = seq.cdr;
+ } else break;
+ }
+ if (cursor) {
+ this.right = cursor.cdr;
+ cursor.cdr = this;
+ return root.optimize(compressor);
+ }
}
}
return this;