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list of javascript cheat sheet

.every(n => ...) => Boolean // ie9+
.some(n => ..) => Boolean   // ie9+

list of javascript cheat sheet

.find(n => ...)  // es6
.findIndex(...)  // es6

list of javascript cheat sheet

// before -- [_,_,NEW,REF,_,_]
list.splice(list.indexOf(REF), 0, NEW))

list of javascript cheat sheet

list = [a,b,c,d,e]

list of javascript cheat sheet

re = list.splice(1)     // re = [b,c,d,e]  list == [a]
re = list.splice(1,2)   // re = [b,c]      list == [a,d,e]

list of javascript cheat sheet

list.push(X)            // list == [_,_,_,_,_,X]
list.unshift(X)         // list == [X,_,_,_,_,_]
list.splice(2, 0, X)    // list == [_,_,X,_,_,_]

list of javascript cheat sheet

// after -- [_,_,REF,NEW,_,_]
list.splice(list.indexOf(REF)+1, 0, NEW))

list of javascript cheat sheet

.filter(n => ...) => array

list of javascript cheat sheet

.map(n => ...)   // ie9+
.reduce((total, n) => total) // ie9+
.reduceRight(...)

Javascript array cheatsheet

// Javascript Array Methods

[3, 4, 5, 6].at(1); // 4
[3, 4, 5, 6].pop(); // [3, 4, 5]
[3, 4, 5, 6].push(7); // [3, 4, 5, 6, 7]
[3, 4, 5, 6].fill(1); // [1, 1, 1, 1]
[3, 4, 5, 6].join("-"); // 3-4-5-6
[3, 4, 5, 6].shift(); // [4, 5, 6]
[3, 4, 5, 6].reverse(); // [6, 5, 4, 3]
[3, 4, 5, 6].unshift(1); // [1, 3, 4, 5, 6]
[3, 4, 5, 6].includes(5); // true
[3, 4, 5, 6].map((num) => num + 6); // [9, 10, 11, 12]
[3, 4, 5, 6].find((num) => num > 4); // 5
[3, 4, 5, 6].filter((num) => num > 4); // [5, 6]
[3, 4, 5, 6].every((num) => num > 5); // false
[3, 4, 5, 6].findeIndex((num) => num > 4); // 2
[3, 4, 5, 6].reduce((acc, num) => acc + num, 0); // 18

list of javascript cheat sheet

list.splice(2, 1, X)    // list == [a,b,X,d,e]

javascript array methods cheat sheet

// example
[ "x", "y", "z" ].join(" - ") // "x - y - z"
// syntax
arr.join([separator])