Question

In this JavaScript, why don’t i get azbc?

var x = "a-b-c".split('-').splice(1, 0, 'z');
alert(x.join(''));

split returns an array containing a, b and c.

Shouldn’t splice insert z after a and gives me azbc?

Why do i get an empty array?

note:
i know that what i want can be accomplished by:

var x = "a-b-c".split('-')
x.splice(1, 0, 'z');
alert(x.join(''));

since splice “modifies” the original array itself. shouldn’t it modify {a,b,c} to {a,z,b,c} and then be assigned to x?

got it… the code below helped me to understand.

var x = "a-b-c".split('-')
x = x.splice(1, 0, 'z');
alert(x.join(''));

Answer 1

splice returns the removed items from the array, not the new array:

> x = 'a-b-c'.split('-');
["a", "b", "c"]
> x.splice(1,0,'z');
[]
> x
["a", "z", "b", "c"]
> x.splice(1,1,'x');
["z"]
> x
["a", "x", "b", "c"]