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let array = [1,2,3,4,5,6,7,8,9,0]
Documentation is something like this
[first, ...rest] = array will output 1 and the rest of array
Now is there a way to take only the first and the last element 1 & 0 with Destructuring
ex: [first, ...middle, last] = array
I know how to take the first and last elements the other way but I was wondering if it is possible with es6
761
To get the first and last elements of an array, access the array at index 0 and the last index. For example, arr[0] returns the first element, whereas arr[arr. length - 1] returns the last element of the array.
To get the last N elements of an array, call the slice method on the array, passing in -n as a parameter, e.g. arr. slice(-3) returns a new array containing the last 3 elements of the original array. Copied!
To access the last n elements of an array, we can use the built-in slice() method by passing -n as an argument to it. n is the number of elements, - is used to access the elements at end of an array.
The rest parameter can only use at the end not anywhere else in the destructuring so it won't work as you expected.
Instead, you can destructor certain properties(an array is also an object in JS), for example, 0 for first and index of the last element for last.
let array = [1,2,3,4,5,6,7,8,9,0]
let {0 : a ,[array.length - 1] : b} = array;
console.log(a, b)Or its better way to extract length as an another variable and get last value based on that ( suggested by @Bergi) , it would work even there is no variable which refers the array.
let {0 : a ,length : l, [l - 1] : b} = [1,2,3,4,5,6,7,8,9,0];
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