How to use the parser-ts.string.spaces function in parser-ts

const isPunctuation = (c: string): boolean => '| =\n():,{};[]->'.indexOf(c) !== -1

const identifierFirstLetter = P.sat(c => !isDigit(c) && !isPunctuation(c))

const identifierBody = P.sat(c => !isPunctuation(c))

/**
 * @since 0.4.0
 */
export const identifier: P.Parser = P.expected(
  S.fold([identifierFirstLetter, C.many(identifierBody)]),
  'an identifier'
)

const leftParens: P.Parser = S.fold([C.char('('), S.spaces])

const rightParens: P.Parser = S.fold([S.spaces, C.char(')')])

const withParens = <a>(parser: P.Parser): P.Parser =&gt; {
  return pipe(
    leftParens,
    P.apSecond(parser),
    P.apFirst(rightParens)
  )
}

const unparametrizedRef: P.Parser = pipe(
  identifier,
  P.map(name =&gt; M.ref(name))
)
</a>

P.chain(name =>
              pipe(
                S.spaces,
                P.apSecond(P.sepBy(S.spaces, parameterDeclaration)),
                P.apFirst(equal),
                P.chain(typeParameters =>
                  pipe(
                    P.sepBy1(pipeParser, constructor),
                    P.map(constructors => M.data(name, typeParameters, constructors)),
                    P.apFirst(S.spaces),
                    P.apFirst(P.eof())
                  )
                )
              )
            )