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takeUntil primitive ​

Signature ​

ts
function takeUntil<T, S>(parser: Parser<T>, terminator: Parser<S>): Parser<[Array<T>, S]>

Description ​

takeUntil combinator applies source parser, collects its output, and stops after terminator parser succeeds. Returns a tuple of values collected by parser and terminator. Fails if parser fails.

Usage ​

ts
const CommentParser = map(
  sequence(string('/*'), takeUntil(any(), string('*/'))),
  (values) => values.flat()
)

const FailingParser = takeUntil(regexp(/\p{Nd}/gu, 'decimal digit'), string('.'))

Success

ts
run(CommentParser).with('/* Hello */')

{
  isOk: true,
  span: [ 0, 11 ],
  pos: 11,
  value: [
    '/*',
    [ ' ', 'H', 'e', 'l', 'l', 'o', ' ' ],
    '*/'
  ]
}

Failure

ts
run(FailingParser).with('one.')

{
  isOk: false,
  span: [ 0, 0 ],
  pos: 0,
  expected: 'decimal digit'
}