map
Creates a new array populated with the results of a provided function on every element.
[1, 2, 3].map( n => n * 2 ); // [2, 4, 6]
filter
Creates a Copy of a portion of a given array, filtered down to just the elements from the given array that pass the test, keep in mind that changes of your first array will affect your copy.
[1,2,3].filter( n => n !== 2 ); // [1,3]
find
Stops and returns the first element in the provided array that satisfies the provided testing function, otherwise returns undefined.
[1,2,3].find( n => n == 2 ) // 2
findIndex
Returns the index of the first element that satisfies the provided testing function. Otherwise -1 is returned.
[1,2,3].findIndex( n => n == 2) // 1
fill
Changes all elements in an array to a static value, from a start index (default 0) to an end index (default array.length). It returns the modified array.
[1,2,3].fill('Txt', 1,2) // [1,'Txt', 3]
every
Tests all elements in the array. After finished returns a Boolean value
[2,2,2].every( n => n == 2 ) // true
some
Tests whether at least one element in the array passes the test implemented by the provided function.
[1,2,3].some( n => n == 2) // true
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Top comments (18)
The code for every has the wrong array I think. Otherwise, a great way of explaining things!
I don't really get the point here pls!
I was thinking this is another version of the example for the every method and atleast the result should be false since not every item is equal to 2.
Got confused with the result of this.answer though!
It had the wrong code initially but the author was diligent enough to change it afterwards.
Alright super!!
Thanks for pointing out.
I like teach with animation!
Fredy,
Nice article - love the animation but I think it could do with two examples for the
everyandsomemethods to demonstrate complete and early exit.Very engaging. I love the gifs
Usefull! Thanks for sharing
Nice way of explaining!
Thanks for creating this. Nice content.
How did you produce those animations ?
Such a great teaching tool
Very Helpful!
excellent content! love it!