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LESS compiler in Java based on less.js

There is a newer version: 1.7.2

/**
 * Copyright (c) 2014 SQUARESPACE, 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.squarespace.less.parse;

import com.squarespace.less.LessException;
import com.squarespace.less.model.Node;


/**
 * A fragment of parsing logic that can be composed into a full
 * parser.  Parselet instances should have no private data, using
 * only the LessStream interface and any static utility methods
 * required.
 *
 * Breaking up the parser this way is for two reasons:
 *
 * 1. Mirroring the same parser structure as less.js. This simplifies
 *    implementing the language and keeping it compatible with
 *    upstream.
 *
 * 2. Writing parser unit tests which can focus completely on
 *    a specific part of the syntax without requiring a lot of
 *    boilerplate, e.g. writing a full mixin when you just want to
 *    test the guard syntax.  This enables more focused and
 *    efficient testing of many edge cases, improving coverage.
 */
public interface Parselet {

  Node parse(LessStream stm) throws LessException;

}