LoMatch

LoMatch is a tool that figures out what Lodash function you should use given an input, desired output, and predicate.

Online Tool

LoMatch isn't likely to live inside of a project, but more likely to be used a few times throughout a project in order to determine what Lodash functions to use. Because of this, I created an online tool to use LoMatch. You will almost always only need to use this tool and not need to install the npm module.

https://www.lomatch.online - please give it some time to load, hosted on the Heroku free tier.

https://lomatch.herokuapp.com as a backup because the domain is expiring late October, 2020 and namecheap wants 35 dang dollarydoos for renewal.

Installation

LoMatch is available as an npm module if you so choose to include it in your project. This is the easiest way to install it:

npm

npm install lomatch

yarn

yarn add lomatch

Usage

const { LoMatch } = require('lomatch');
let results = LoMatch(input, output, primers);
console.log(results);

input - an object, array, or string that you currently have output - the desired format you want your data in primers - an array of values that you think will help LoMatch figure out a result results - an array of objects containing a func and args that when in combination with your input can get you to your output

Examples below

Arrays

Example

I have a starting array of [1, 2, 3, 2, 2], and I want a final array of [1, 3]. I don't know which Lodash functions I need to use in order to get there, so I'll use LoMatch!

const { LoMatch } = require('lomatch');
LoMatch([1, 2, 3, 2, 2], [1, 3], []);

This will return an output of all the Lodash functions and predicate combinations you should use (only one 'smallest' predicate per function).

[ { func: '_.difference', args: [ 2 ] },
  { func: '_.differenceBy', args: [ 2 ] },
  { func: '_.differenceWith', args: [ 2 ] },
  { func: '_.intersection', args: [ 1, 3 ] },
  { func: '_.intersectionBy', args: [ 1, 3 ] },
  { func: '_.intersectionWith', args: [ 1, 3 ] },
  { func: '_.pull', args: 2 },
  { func: '_.pullAll', args: [ 2 ] },
  { func: '_.pullAllBy', args: [ 2 ] },
  { func: '_.pullAllWith', args: [ 2 ] },
  { func: '_.pullAt', args: [ 0, 2 ] },
  { func: '_.without', args: 2 },
  { func: '_.xor', args: [ 2 ] },
  { func: '_.xorBy', args: [ 2 ] },
  { func: '_.xorWith', args: [ 2 ] } ]

This means that you can use something like _.pull([1, 2, 3, 2, 2], 2) in order to get [1, 3]. LoMatch will return results for both modified arrays and returned arrays. Be sure to read the Lodash documentation for the function you are going to use.

Objects

Example

I have a starting object of { 'a': [{ 'b': { 'c': 3 } }, 4] }, and I want a final array of [3, 4].

const { LoMatch } = require('lomatch');
LoMatch({ 'a': [{ 'b': { 'c': 3 } }, 4] }, [3, 4], []);

This will return an output of all the Lodash functions and predicate combinations you should use.

[ { func: '_.at', args: [ 'a[0].b.c', 'a[1]' ] } ]

This means that you can use _.at({ 'a': [{ 'b': { 'c': 3 } }, 4] }, [ 'a[0].b.c', 'a[1]' ]) in order to get [3, 4]. LoMatch will return results for both modified objects and returned objects. Be sure to read the Lodash documentation for the function you are going to use.

Strings

While strings are supported by LoMatch, there will only in rare cases be more than one solution.

Example

I have a starting string of 'fred, barney, & pebbles', and I want a final array of ['fred', 'barney', 'pebbles'].

const { LoMatch } = require('lomatch');
LoMatch('fred, barney, & pebbles', ['fred', 'barney', 'pebbles'], []);

This will return an output of all the Lodash functions and predicate combinations you should use.

[ { func: '_.words', args: [] } ]

This means that you can use _.words('fred, barney, & pebbles') in order to get ['fred', 'barney', 'pebbles']. Keep in mind strings are primitives and thus cannot be mutated in JavaScript. Be sure to read the Lodash documentation for the function you are going to use.