combine predicates

combine-predicates.js

import { isFunction } from 'lodash'

export default function combinePredicates(...predicates) {
  predicates = predicates.filter(isFunction)
  const n = predicates.length
  return n === 0
    ? undefined
    : n === 1
    ? predicates[0]
    : function() {
        for (let i = 0; i < n; ++i) {
          if (!predicates[i].apply(this, arguments)) {
            return false
          }
        }
        return true
      }
}