filter-map

Array utility to help writing filter/map separately without struggling with reduce

Description

Have you ever experienced writing filtering and mapping over an array at the same time? will you go for this way:

constres=[1,2,3,4,5].filter(it=>it%2===0).map(it=>it**3)// Two iterationsconsole.log(res)// [8, 64]

Then I guess you have a colleague that adds a review comment to use Array's reduce to perform less iterations. Why bother writing it with reduce when you can do:

constres=[1,2,3,4,5].filterMap(it=>it%2===0,it=>it**3)// One iterationconsole.log(res)// [8, 64]

Installing

npm i -S @jamiri/filter-map

or

yarn add @jamiri/filter-map

Importing

Nodejs

require('filter-map')console.log([1,2,3].filterMap(x=>x>1,x=>x*3))

Webpack

import'filter-map'console.log([1,2,3].filterMap(x=>x>1,x=>x*3))

Api

Upon requireing/importing the package following functions are added to the array prototype

filterMap(filterFn, mapFn)
mapFilter(mapFn, filterFn)

These are now available on instances of arrays i.e. all arrays from there on.