com.google.gwt.dev.js.ast.JsUnaryOperator Maven / Gradle / Ivy
/*
* Copyright 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
* in compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License
* is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
* or implied. See the License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.gwt.dev.js.ast;
/**
* A JavaScript unary operator.
*/
public enum JsUnaryOperator implements JsOperator {
/*
* Precedence indices from "JavaScript - The Definitive Guide" 4th Edition (page 57)
*/
BIT_NOT("~", 14, PREFIX), DEC("--", 14, POSTFIX | PREFIX), DELETE("delete", 14, PREFIX), INC(
"++", 14, POSTFIX | PREFIX), NEG("-", 14, PREFIX), POS("+", 14, PREFIX), NOT("!", 14, PREFIX), TYPEOF(
"typeof", 14, PREFIX), VOID("void", 14, PREFIX);
private final int mask;
private final int precedence;
private final String symbol;
private JsUnaryOperator(String symbol, int precedence, int mask) {
this.symbol = symbol;
this.precedence = precedence;
this.mask = mask;
}
@Override
public int getPrecedence() {
return precedence;
}
@Override
public String getSymbol() {
return symbol;
}
@Override
public boolean isKeyword() {
return this == DELETE || this == TYPEOF || this == VOID;
}
@Override
public boolean isLeftAssociative() {
return (mask & LEFT) != 0;
}
public boolean isModifying() {
return this == DEC || this == INC || this == DELETE;
}
@Override
public String toString() {
return symbol;
}
}