Index an array of arrays with an array of indexes in javascript

Question

Given an array of arrays [of arrays ...] such as:

array[a][b][c][d][e]

And an array of indexes:

indexes = [ a, b, c, d, e ];

Is there an elegant way to index the array of arrays using the array of indexes?

The brute force method I am using is:

element = array[indexes[0]][indexes[1]][indexes[2]][indexes[3]][indexes[4]]

EDIT

To be clear, I would to be able to use an arbitrary array of indexes from 1 to n elements, where n is the depth of array nesting.

So given the above example of five-level nested array of arrays, and given an index array of:

indexes2 = [ a, b, c ];

I would expect to retrieve:

array[a][b][c]

gen_Eric · Accepted Answer · 2015-10-21 17:07:52Z

3

You can use Array.reduce() to go through the indexes and get the element you want.

// array[a][b][c][d][e]
var indexes = [ a, b, c, d, e ];

var element = indexes.reduce(function(prev, curr){
    return prev[curr];
}, array);

answered Oct 21, 2015 at 17:07

gen_Eric

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1 Comment

That appears to do the job exactly, and is not likely a solution I would have stumbled onto on my own. Thank you.