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My Javascript notes, stuff that I use often in the curent project I'm working on

For loop

let iterable = [1, 2, 3];
for(let value of iterable) { consol­e.l­og(­value); }

Slice VS Splice

slice
shallow
splice
changes
The slice() method retrurns a shallow copy of a portion of an array into a new array object:
arr.slice([begin[, end]])

The splice method changes the content of an array by removing existing elements and/or adding new elements.
arr.sp­lic­e(s­tart, delete­Count [, item1 [, item2 ...]])

Chomp string

string = string.slice(0, -1);

Strings: substr VS substring

string.su­bst­r(s­tart, length)
string.su­bst­rin­g(s­tart, stop)
 

Clonin­g/A­ssi­gnment

Object.as­sig­n(obj1, obj2);
to clone:
let clone = Object.as­sig­n({}, obj1); // Though not sure if swallow or deep copy

"­Fal­sy" values in JS

Undefined
 
null
 
false
 
+0
, 
-0
, and 
NaN
 
"­"
 

Array aggreg­ation

array1 = array1.concat(array2);

Array includes element

array1.includes('xyz')

Case insens­itive compar­isson

(a, b) => a.toLowerCase().localeCompare(b.toLowerCase())

Logging companions

http:/­/1l­ine­art.ku­lao­ne.c­om/#/
http:/­/ba­da5­5.io/

For something like:
consol­e.l­og(­'%cd[ o_0 ]b %s', 'color: #fa5732;', 'DATA');

(always) Thanks to MDN
 

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  • Published: 21st September, 2016
  • Last Updated: 1st January, 2017
  • Rated: 5 out of 5 stars based on 3 ratings

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Lavysh

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