Array inside Array and $.map()

Question

I try to learn jQuery.map() and something i misunderstand

Why...

var arr = [0];
arr = $.map(arr, function(a,i) {
  return [a,i];
});

Return [0, 0] ,Why not [[0,0]]

but normally

var arr = [0];
arr = [arr,0];

Return [[0], 0]

Seems like stupid qustion, But expain me pls

freejosh · Accepted Answer · 2013-08-01 13:21:42Z

4

The documentation for the callback in jQuery 1.6+ says:

A returned array will be flattened into the resulting array

Which basically means that if your map results in a nested array, the nesting will be discarded and a single-dimension array will be returned.

answered Aug 1, 2013 at 13:21

freejosh

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