38 lines
1.1 KiB
JavaScript
38 lines
1.1 KiB
JavaScript
'use strict';
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var $TypeError = require('es-errors/type');
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var IsArray = require('./IsArray');
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var IsInteger = require('./IsInteger');
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var every = require('../helpers/every');
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var regexTester = require('safe-regex-test');
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var isChar = function isChar(c) {
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return typeof c === 'string' && c.length === 1;
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};
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var isWordCharacter = regexTester(/^[a-zA-Z0-9_]$/);
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// https://262.ecma-international.org/6.0/#sec-runtime-semantics-iswordchar-abstract-operation
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// note: prior to ES2023, this AO erroneously omitted the latter of its arguments.
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module.exports = function IsWordChar(e, InputLength, Input) {
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if (!IsInteger(e)) {
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throw new $TypeError('Assertion failed: `e` must be an integer');
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}
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if (!IsInteger(InputLength)) {
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throw new $TypeError('Assertion failed: `InputLength` must be an integer');
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}
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if (!IsArray(Input) || !every(Input, isChar)) {
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throw new $TypeError('Assertion failed: `Input` must be a List of characters');
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}
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if (e === -1 || e === InputLength) {
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return false; // step 1
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}
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var c = Input[e]; // step 2
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return isWordCharacter(c); // steps 3-4
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};
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