package.json

{
  "name": "transduce",
  "version": "0.1.0",
  "main": "transduce.js",
  "license": "MIT",
  "author": {
    "name": "m3g4p0p"
  }
}

transduce.js

export const pipe = (...fns) => value => fns.reduce((result, current) => current(result), value)

export const curry = fn => function accumulate () {
  return arguments.length < fn.length
    ? accumulate.bind(this, ...arguments)
    : fn.apply(this, arguments)
}

export const append = (array, ...values) => array.concat(values)

export const appendUnique = (array, ...values) =>
  array.concat(
    values.filter(value =>
      array.indexOf(value) === -1
    )
  )

export const makeFilterReducer = curry(
  (predicate, combine) =>
    (result, current) =>
      predicate(current)
        ? combine(result, current)
        : result
)

export const makeMapReducer = curry(
  (mapper, combine) =>
    (result, current) =>
      combine(result, mapper(current))
)

export const transduce = curry(
  (transducer, transformer, initial, values) =>
    values.reduce(transducer(transformer), initial)
)

export const makeTapTransducer = curry(
  (callback, combine) =>
    (...args) => {
      callback(null, ...args)
      return combine(...args)
    }
)

export const deepFlatTransducer = combine =>
  (result, current) =>
    current != null && current[Symbol.iterator]
      ? transduce(deepFlatTransducer, combine, result)(current)
      : combine(result, current)