/*jshint node:true */
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/*
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The MIT License (MIT)
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Copyright (c) 2007-2018 Einar Lielmanis, Liam Newman, and contributors.
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Permission is hereby granted, free of charge, to any person
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obtaining a copy of this software and associated documentation files
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(the "Software"), to deal in the Software without restriction,
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including without limitation the rights to use, copy, modify, merge,
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publish, distribute, sublicense, and/or sell copies of the Software,
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and to permit persons to whom the Software is furnished to do so,
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subject to the following conditions:
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The above copyright notice and this permission notice shall be
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included in all copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.
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*/
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'use strict';
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function TokenStream(parent_token) {
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// private
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this.__tokens = [];
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this.__tokens_length = this.__tokens.length;
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this.__position = 0;
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this.__parent_token = parent_token;
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}
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TokenStream.prototype.restart = function() {
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this.__position = 0;
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};
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TokenStream.prototype.isEmpty = function() {
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return this.__tokens_length === 0;
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};
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TokenStream.prototype.hasNext = function() {
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return this.__position < this.__tokens_length;
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};
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TokenStream.prototype.next = function() {
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var val = null;
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if (this.hasNext()) {
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val = this.__tokens[this.__position];
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this.__position += 1;
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}
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return val;
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};
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TokenStream.prototype.peek = function(index) {
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var val = null;
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index = index || 0;
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index += this.__position;
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if (index >= 0 && index < this.__tokens_length) {
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val = this.__tokens[index];
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}
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return val;
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};
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TokenStream.prototype.add = function(token) {
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if (this.__parent_token) {
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token.parent = this.__parent_token;
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}
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this.__tokens.push(token);
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this.__tokens_length += 1;
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};
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module.exports.TokenStream = TokenStream;
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