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'use strict'; |
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const types = require('../../../tokenizer/types.cjs'); |
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const LESSTHANSIGN = 60; |
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const EQUALSIGN = 61; |
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const GREATERTHANSIGN = 62; |
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const structure = { |
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left: ['Identifier', 'Number', 'Dimension', 'Ratio'], |
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leftComparison: String, |
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middle: ['Identifier', 'Number', 'Dimension', 'Ratio'], |
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rightComparison: [String, null], |
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right: ['Identifier', 'Number', 'Dimension', 'Ratio', null] |
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}; |
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function readTerm() { |
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this.skipSC(); |
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switch (this.tokenType) { |
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case types.Number: |
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if (this.lookupNonWSType(1) === types.Delim) { |
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return this.Ratio(); |
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} else { |
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return this.Number(); |
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} |
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case types.Dimension: |
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return this.Dimension(); |
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case types.Ident: |
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return this.Identifier(); |
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default: |
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this.error('Number, dimension, ratio or identifier is expected'); |
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} |
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} |
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function readComparison(expectColon) { |
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this.skipSC(); |
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if (this.isDelim(LESSTHANSIGN) || |
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this.isDelim(GREATERTHANSIGN)) { |
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const value = this.source[this.tokenStart]; |
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this.next(); |
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if (this.isDelim(EQUALSIGN)) { |
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this.next(); |
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return value + '='; |
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} |
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return value; |
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} |
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if (this.isDelim(EQUALSIGN)) { |
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return '='; |
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} |
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this.error(`Expected ${expectColon ? '":", ' : ''}"<", ">", "=" or ")"`); |
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} |
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function createParse(type) { |
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return function parse() { |
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const start = this.tokenStart; |
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this.skipSC(); |
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this.eat(types.LeftParenthesis); |
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const left = readTerm.call(this); |
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const leftComparison = readComparison.call(this, left.type === 'Identifier'); |
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const middle = readTerm.call(this); |
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let rightComparison = null; |
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let right = null; |
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if (this.lookupNonWSType(0) !== types.RightParenthesis) { |
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rightComparison = readComparison.call(this); |
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right = readTerm.call(this); |
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} |
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this.skipSC(); |
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this.eat(types.RightParenthesis); |
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return { |
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type, |
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loc: this.getLocation(start, this.tokenStart), |
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left, |
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leftComparison, |
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middle, |
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rightComparison, |
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right |
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}; |
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}; |
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} |
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function generate(node) { |
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this.token(types.LeftParenthesis, '('); |
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this.node(node.left); |
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this.tokenize(node.leftComparison); |
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this.node(node.middle); |
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if (node.right) { |
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this.tokenize(node.rightComparison); |
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this.node(node.right); |
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} |
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this.token(types.RightParenthesis, ')'); |
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} |
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exports.createParse = createParse; |
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exports.generate = generate; |
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exports.structure = structure; |
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