Produce By Path - New JavaScript Design Pattern

Description

Produce By Path is a design pattern, which is used to dynamically produce values by using the path to which it is applied.

Installation

npm install produce-by-path

Usage

import ProduceByPath from "produce-by-path"
// CommonJS usage
// const ProduceByPath = require("produce-by-path")


// define producer instance to our liking :)
const instance = new ProduceByPath({
    call: (path, args) => {
        return ({
            path,
            args,
        })
    },
    toPrimitive: (path, hint) => {
        return path.join("--")
    }
})


//      Now we can apply the [[instance]] object with any properties
//      combination and call as a function and receive the desired
//      result as we defined in the [[call]] handler.
console.log( instance.I.love.you("arg1", "arg2") )  
//      {
//          path: ["I", "love", "you"],
//          args: ["arg1", "arg2"]
//      } 


//      We can also apply the [[instance]] object with any properties
//      combination and convert as a primitive value and receive
//      the desired result as we defined in [[toPrimitive]] handler.
console.log( String(instance.I.love.you) )
//      I--love--you

console.log( instance.I.love.you + '')
//      I--love--you

Why should I use an ProduceByPath pattern?

Using that pattern in some cases we can build a simple and intuitive interface for my software.

For example, the redux-cool library use that pattern for making action objects.

import {actionsCreator} from "redux-cool"


const first_action = actionsCreator.MY.FIRST.ACTION("arg1", "arg2")
console.log(first_action)
//      {
//          type: "MY/FIRST/ACTION",
//          args: ["arg1", "arg2"],
//          cb: f() identity,
//          _index: 1
//      } 

const second_action = actionsCreator.This.is.my.second.action(2021)
console.log(second_action)
//      {
//          type: "This/is/my/second/action",
//          args: [2021],
//          cb: f() identity,
//          _index: 2
//      } 



//      If we just need to generate an action type as a string,
//      we can do it easily
const type1 = String(actionsCreator.MY.FIRST.ACTION)
console.log(type1)
//      "MY/FIRST/ACTION"

//      or any string conversion
const type2 = actionsCreator.MY.FIRST.ACTION + ""
console.log(type2)
//      "MY/FIRST/ACTION"

Links

npm
github
redux-cool actionsCreator