React state management. clean sate mess, loading and error handling in react
Photo by Unsplash


React Rendering javascript data types
{props.heroList.length && <HeroListContainer list={list} />}


terminal commands, shell commands, linux terminal
Photo by Joshua Sortino on Unsplash
  • cat
  • cut
  • tail/head
  • grep
  • history / !<command number>
  • !<command you last used> it will remember the other parameters
  • Paste will join data from the files

What other wildcards can I use?

  • ? matches a single character, so 201?.txt will match 2017.txt or 2018.txt, but not 2017-01.txt.
  • [...] matches any one of the characters inside the square brackets, so 201[78].txt matches 2017.txt or 2018.txt, but not 2016.txt.
  • {...} matches any…


  1. A component should be camelCased.
  2. Component composition or content projection in Angular achieved using
    `props.children`
  3. some changes in HTML htmlfor, className
  4. Special prop key which is used for array iteration and isn’t accessible in the component.
  5. Special template Fragment used to hold elements shorthand for this is <></> .
  6. For forms management user Formik as handling forms are tuff.
  7. for styling user camelCase e.g. styles={backgroudColor: 'red'}
  8. ref to manipulate HTML element in the components programmatically.
  9. Lazy component loading…


  1. About the data types supported in the jsx .
  • numbers/ string
  • Array
  • Set
  • any iterables
// this is valid jsxconst testVar = new Set([2,3,3,4]);function App() {return (<div className="App"><h1>Hello CodeSandbox</h1><h2>Start editing to see some magic happen!</h2><button onClick={()=>console.log(window.location.reload())} >Test</button>{(testVar)} {`testVar Hellot ${testVar} {good for the printing}`}{ `Hello {testVar}` }</div>);}
// use template literal string for this 
// if you want to print {myVar} in jsk. do it this way
return <div>
{ `{myVar} // will print…

Python shell/python cmd command`

python -c "print('Hello!')"
> Hello!
python -m pdb mycode.py
Python string and indexes


Photo by Science in HD on Unsplash
<iclass="fa fa-lg fa-fw"[ngClass]="{'fa-check-square text-primary': vendor.id,'fa-window-close text-danger': !vendor.id}"></i>
<iclass="fa fa-lg fa-fw"[ngClass]="{'fa-check-square text-primary': collection.includes(vendor.id),'fa-window-close text-danger': !collection.includes(vendor.id)}"


New web APIs

<li routerLinkActive="active activeClass2">
<a routerLink="/page">Inicio</a>
</li>


  • Python
  • R
  • Scala
  • SQL / Hive context

Lokesh kumar Jain

Love Web building technologies working as frontend team lead loves working on JavaScript tech stack, as Reactjs, Angular, HTML5

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store