48 lines
1.1 KiB
JavaScript
48 lines
1.1 KiB
JavaScript
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import {start as startRe, cont as contRe} from './regex.js'
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/**
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* Checks if the given character code can start an identifier.
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*
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* @param {number} code
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* Character code to check.
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* @returns {boolean}
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* Whether `code` can start an identifier.
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*/
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// To do: support astrals.
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export function start(code) {
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return startRe.test(String.fromCharCode(code))
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}
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/**
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* Checks if the given character code can continue an identifier.
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*
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* @param {number} code
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* Character code to check.
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* @returns {boolean}
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* Whether `code` can continue an identifier.
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*/
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// To do: support astrals.
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export function cont(code) {
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const character = String.fromCharCode(code)
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return startRe.test(character) || contRe.test(character)
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}
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/**
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* Checks if the given value is a valid identifier name.
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*
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* @param {string} name
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* Identifier to check.
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* @returns {boolean}
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* Whether `name` can be an identifier.
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*/
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export function name(name) {
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let index = -1
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while (++index < name.length) {
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if (!(index ? cont : start)(name.charCodeAt(index))) return false
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}
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// `false` if `name` is empty.
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return index > 0
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}
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