JavaScript Array Methods

SofienDerbel
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#JavaScript Array Methods

[2,3,4,5].at(1)         // 3 ,  returns you the element with index 1.
[2,3,4,5].pop()         // [2,3,4] ,  removes the last element.
[2,3,4,5].push(6)       // [2,3,4,5,6] ,  adds the element at the last position.
[2,3,4,5].fill(1)       // [1,1,1,1] , fills all the array values.
[2,3,4,5].join('-')     // '2-3-4-5' , concatinates all the elements with the char passed in arg.
[2,3,4,5].shift()       // [3,4,5] , deletes the first element.
[2,3,4,5].reverse()     // [5,4,3,2] , reverses the array.
[2,3,4,5].unshift(1)    // [1,2,3,4,5] , adds new elements to the beginning of an array.
[2,3,4,5].includes(5)   // true , returns true if an array contains a specified value. / false if not found
[2,3,4,5].map((num) => num + 6 ) // [9,10,11,12] , allows you to iterate over an array and modify its elements using a callback function. 
[2,3,4,5].find((num) => num > 4 ) // 5 , returns the value of the first element that passes a test.
[2,3,4,5].some((num) => num > 5 ) // true , tests whether at least one element in the array passes the test implemented by the provided function.
[2,3,4,5].filter((num) => num > 4 ) // [5,6] , creates a new array filled with elements that pass a test provided by a function.
[2,3,4,5].every((num) => num > 5 ) // false , executes a function for each array element.
[2,3,4,5].findindex((num) => num > 4 ) // 2 ,  returns the index of a first array element that satisfies the provided condition.
[2,3,4,5].reduce((acc,num) => acc+num ) // 18 , returns a single value: the function's accumulated result.
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