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mapTo composite

Signature

ts

function mapTo<T, R>(parser: Parser<T>, value: R): Parser<R>

Description

mapTo combinator maps the parser's result to a constant value.

Usage

ts

const Parser = mapTo(
  sequence(integer(), string('+'), integer()),
  5
)

Success

ts

run(Parser).with('2+2')

{
  isOk: true,
  span: [ 0, 3 ],
  pos: 3,
  value: 5
}

Failure

ts

run(Parser).with('2-2')

{
  isOk: false,
  span: [ 1, 2 ],
  pos: 2,
  expected: '+'
}