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Safedom - A Pure Way to Manipulate the DOM

 3 years ago
source link: https://www.tuicool.com/articles/hit/AJreMb2
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safedom

safedom is a safe way to you manipulate dom using a purer functional style.

Table of Contents

Installation

safedom is available from npm .

$ npm install safedom -S

Why safedom ?

In many applications most of the errors are still related to DOM manipulations, and as we are dealing with side effects, we need to have null checks, but safedom lets you do this safely. All safe functions are automatically curried and emphasizes a purer functional style.

Overview

//<div id="app" data-value="10">hello world</div>
const safedom = require('safedom')
const value = safedom.select('#app')
  .chain(safedom.getAttr('data-value'))
  .map(eff => eff.value)
  .map(parseInt)
   map(value => value + 100)
  .getOrElse(0)

console.log(value) // 110

A wonderful error messages

It's good to know where it's not working, for example

  1. Select by Id but is not found in DOM
//<div id="dragon" data-value="10">hello world</div>
const safedom = require('safedom')

safedom.select('#apslkajdp')
  .chain(safedom.getAttr('data-value'))
  .map(eff => eff.value)
  .map(parseInt)
  .map(value => value + 100)
  .matchWith({
    Ok: ({ value }) => value,
    
    Error: ({ value: error }) => {
      console.log(error)
      /*
        Selector: '#apslkajdp' dont found 
        Method: select
      */
    }
  })
  1. Get an attribute from a element but dont have
//<div id="dragon">hello world</div>
const safedom = require('safedom')

const value = safedom.select('#dragon')
  .chain(safedom.getAttr('data-value'))
  .map(eff => eff.value)
  .map(parseInt)
  .matchWith({
    Ok: ({ value }) => value,
    
    Error: ({ value: error }) => {
      console.log(error)
      /*
        Attribute: 'data-value' don't found 
        Node: [object HTMLDivElement]
        Method: getAttr
      */
    }
  })

Documentation

select

Similiar to a document.querySelector but returns a Result monad from folktale .

You can use methods available to manipulate value.

//<div id="dragon">hello world</div>
const safedom = require('safedom')

const value = safedom.select('#dragon')
console.log(value) //InternalConstructor {value: div#app}

To you get value in safe way, you should map value.

//<div id="dragon">hello world</div>
const safedom = require('safedom')

const value = safedom.select('#dragon')
  .map(element => element.textContent)
  .map(console.log)
  
console.log(value) //hello world

You can have a default value for when you can't find.

//<div id="dragon">hello world</div>
const safedom = require('safedom')

const value = safedom.select('#lion')
  .map(element => element.textContent)
  .getOrElse('Victor')

console.log(value) //Victor

selectAll

Similiar to an document.querySelectorAll but returns a Result monad from folktale . But querySelectorAll returns a NodeList and safedom, a Array.

You can use methods available to manipulate value.

//<div id="dragon">hello world</div>
const safedom = require('safedom')

const value = safedom.selectAll('#dragon')
console.log(value)//InternalConstructor [{value: div#app}]

getAttr

Similiar to a node.getAttribute but returns a Result monad from folktale .

//<div id="app" data-value="10">hello world</div>
const safedom = require('safedom')
const value = safedom.select('#app')
  .chain(safedom.getAttr('data-value')) //should use chain because getAttr returns a Result
  .map(eff => eff.value)
  .map(parseInt)
   map(value => value + 100)
  .getOrElse(0)

console.log(value) // 110

disable

You can disable specific element

//<div id="app">hello world</div>
const safedom = require('safedom')
const value = safedom.disable('#app')

console.log(value)// InternalConstructor {value: div#app.disabled}
//<div id="app">hello world</div>
const safedom = require('safedom')
const value = safedom.disable('#app')
  .map((el) => {
    console.log(e) 
    //<div id="app" class="disabled" readonly="true" aria-disabled="true"> Victor </div>
    return el
  })

enable

Just enable specific element

//<div id="app" class="disabled" readonly="true" aria-disabled="true"> Victor </div>
const safedom = require('safedom')
const value = safedom.enable('#app')

console.log(value)// InternalConstructor {value: div#app}
//<div id="app" class="disabled" readonly="true" aria-disabled="true"> Victor </div>
const safedom = require('safedom')
const value = safedom.enable('#app')
  .map((el) => {
    console.log(e) 
    //<div id="app">hello world</div>
    return el
  })

on

Handle DOM-events

const handleClick = () => console.log('clicked')
safedom.on('click', document, handleClick)
const handleClick = () => console.log('clicked')
safedom.select('#app')
 .map(safedom.on('click'))
 .map(clickStream => clickStream(handleClick))

License

The code is available under the MIT License .


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