if (!property) return expression;
return make_sequence(this, [ expression, property ]);
});
- def(AST_SymbolRef, function(compressor) {
- return this.is_declared(compressor) && all(this.definition().orig, function(sym) {
+ function drop_symbol(ref) {
+ return all(ref.definition().orig, function(sym) {
return !(sym instanceof AST_SymbolConst);
- }) ? null : this;
+ });
+ }
+ def(AST_SymbolRef, function(compressor) {
+ return this.is_declared(compressor) && drop_symbol(this) ? null : this;
});
def(AST_This, return_null);
def(AST_Unary, function(compressor, first_in_statement) {
+ var exp = this.expression;
if (unary_side_effects[this.operator]) {
- this.write_only = !this.expression.has_side_effects(compressor);
+ this.write_only = !exp.has_side_effects(compressor);
return this;
}
- if (this.operator == "typeof" && this.expression instanceof AST_SymbolRef) return null;
- var expression = this.expression.drop_side_effect_free(compressor, first_in_statement);
- if (first_in_statement && expression && is_iife_call(expression)) {
- if (expression === this.expression && this.operator == "!") return this;
- return expression.negate(compressor, first_in_statement);
+ if (this.operator == "typeof" && exp instanceof AST_SymbolRef) {
+ if (drop_symbol(exp)) return null;
+ if (exp.is_declared(compressor)) return exp;
}
- return expression;
+ var node = exp.drop_side_effect_free(compressor, first_in_statement);
+ if (first_in_statement && node && is_iife_call(node)) {
+ if (node === exp && this.operator == "!") return this;
+ return node.negate(compressor, first_in_statement);
+ }
+ return node;
});
})(function(node, func) {
node.DEFMETHOD("drop_side_effect_free", func);