kefir/src/many-sources/flat-map-errors.js

Reactive Programming library for JavaScript inspired by Bacon.js and RxJS with focus on high performance and low memory usage

import {VALUE, ERROR, END} from '../constants'
import {inherit} from '../utils/objects'
import FlatMap from './flat-map'

function FlatMapErrors(source, fn) {
  FlatMap.call(this, source, fn)
}

inherit(FlatMapErrors, FlatMap, {
  // Same as in FlatMap, only VALUE/ERROR flipped
  _handleMain(event) {
    if (event.type === ERROR) {
      let sameCurr = this._activating && this._hadNoEvSinceDeact && this._lastCurrent === event.value
      if (!sameCurr) {
        this._add(event.value, this._fn)
      }
      this._lastCurrent = event.value
      this._hadNoEvSinceDeact = false
    }

    if (event.type === VALUE) {
      this._emitValue(event.value)
    }

    if (event.type === END) {
      if (this._isEmpty()) {
        this._emitEnd()
      } else {
        this._mainEnded = true
      }
    }
  },
})

export default FlatMapErrors