oneOf

oneOf ensures that one of the characters in the given string matches the current character. Characters are compared as whole code points, so surrogate pairs are matched intact. At the end of input it fails with oneOf @ reached the end of input instead of the usual one of: ... message.

Usage

const Parser = oneOf('xyz')

Success

run(Parser).with('y-combinator')

{
  isOk: true,
  start: 0,
  end: 1,
  pos: 1,
  value: 'y'
}

Failure

run(Parser).with('q-combinator')

{
  isOk: false,
  start: 0,
  end: 0,
  pos: 0,
  expected: 'one of: x, y, z'
}