68 lines
1.5 KiB
JavaScript
68 lines
1.5 KiB
JavaScript
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/**
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* @import {Effects, State, TokenType} from 'micromark-util-types'
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*/
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import {markdownSpace} from 'micromark-util-character'
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// To do: implement `spaceOrTab`, `spaceOrTabMinMax`, `spaceOrTabWithOptions`.
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/**
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* Parse spaces and tabs.
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*
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* There is no `nok` parameter:
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*
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* * spaces in markdown are often optional, in which case this factory can be
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* used and `ok` will be switched to whether spaces were found or not
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* * one line ending or space can be detected with `markdownSpace(code)` right
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* before using `factorySpace`
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*
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* ###### Examples
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*
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* Where `␉` represents a tab (plus how much it expands) and `␠` represents a
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* single space.
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*
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* ```markdown
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* ␉
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* ␠␠␠␠
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* ␉␠
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* ```
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*
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* @param {Effects} effects
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* Context.
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* @param {State} ok
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* State switched to when successful.
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* @param {TokenType} type
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* Type (`' \t'`).
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* @param {number | undefined} [max=Infinity]
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* Max (exclusive).
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* @returns {State}
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* Start state.
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*/
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export function factorySpace(effects, ok, type, max) {
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const limit = max ? max - 1 : Number.POSITIVE_INFINITY
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let size = 0
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return start
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/** @type {State} */
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function start(code) {
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if (markdownSpace(code)) {
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effects.enter(type)
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return prefix(code)
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}
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return ok(code)
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}
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/** @type {State} */
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function prefix(code) {
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if (markdownSpace(code) && size++ < limit) {
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effects.consume(code)
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return prefix
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}
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effects.exit(type)
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return ok(code)
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}
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}
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