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* Copyright (C) Codehaus.org *
* ------------------------------------------------------------------------- *
* 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, *
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package net.ion.rosetta;
final class PeekParser<T> extends Parser<T> {
private final Parser<T> parser;
PeekParser(Parser<T> parser) {
this.parser = parser;
}
@Override
boolean apply(ParseContext ctxt) {
int step = ctxt.step;
int at = ctxt.at;
boolean ok = parser.run(ctxt);
if (ok)
ctxt.setAt(step, at);
return ok;
}
@Override
public String toString() {
return "peek";
}
}