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