37 lines
954 B
JavaScript
37 lines
954 B
JavaScript
var Token = require('../../tokenizer/token');
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var serializeBody = require('../../writer/one-time').body;
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var serializeRules = require('../../writer/one-time').rules;
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function removeDuplicates(tokens) {
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var matched = {};
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var moreThanOnce = [];
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var id, token;
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var body, bodies;
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for (var i = 0, l = tokens.length; i < l; i++) {
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token = tokens[i];
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if (token[0] != Token.RULE) { continue; }
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id = serializeRules(token[1]);
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if (matched[id] && matched[id].length == 1) { moreThanOnce.push(id); } else { matched[id] = matched[id] || []; }
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matched[id].push(i);
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}
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for (i = 0, l = moreThanOnce.length; i < l; i++) {
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id = moreThanOnce[i];
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bodies = [];
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for (var j = matched[id].length - 1; j >= 0; j--) {
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token = tokens[matched[id][j]];
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body = serializeBody(token[2]);
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if (bodies.indexOf(body) > -1) { token[2] = []; } else { bodies.push(body); }
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}
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}
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}
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module.exports = removeDuplicates;
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