var myArray =[], name;?

Question

What purpose does name have in the following statement?

var myArray =[], name;

I usually initialize my arrays as the following:

var myArray =[];

score 18 · Answer 1 · edited May 23 '17 at 12:08

18

It is shorthand to

var myArray =[];
var name;

It is matter of personal preference.

edited May 23 '17 at 12:08

Community

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answered Jun 03 '11 at 21:18

amit_g

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this is not technically true, is it? Wouldn't the scoping of name be global even if it were defined in a function? – ShaneBlake Jun 03 '11 at 21:25
@ShaneBlake absolutely not - exactly the opposite in fact. – Pointy Jun 03 '11 at 21:27
4

@ShaneBlake - As long as `name` is declared with `var` it will be scoped within the current scope be it global or function. – ChaosPandion Jun 03 '11 at 21:27
@ShaneBlake, the style of writing in these two ways doesn't impact anything about the scope. – amit_g Jun 03 '11 at 21:29
Downvoter, would you please let me know why it was downvoted so that it can be improved/corrected? – amit_g Jun 04 '11 at 19:26

score 11 · Answer 2 · answered Jun 03 '11 at 21:19

11

You are actually initialising two variables there, myArray and name.

You set myArray to [] and name to undefined, because you don't give any value.

Your code is equivalent to this:

var myArray = [];
var name;

answered Jun 03 '11 at 21:19

lonesomeday

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score 8 · Answer 3 · answered Jun 03 '11 at 21:19

8

It is equal to this:

var myArray =[];
var name;

answered Jun 03 '11 at 21:19

aorcsik

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score 8 · Answer 4 · answered Jun 03 '11 at 21:20

8

In JavaScript multiple variable assignments can be separated by commas, eliminating the need for repetitive var statements.

var myArray = [];
var name;

is equivalent to

var myArray = [], name;

answered Jun 03 '11 at 21:20

g.d.d.c

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score 7 · Answer 5 · answered Jun 03 '11 at 21:19

7

This is equivalent to

var myArray =[];
var name;

answered Jun 03 '11 at 21:19

trutheality

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score 7 · Answer 6 · answered Jun 03 '11 at 21:19

7

It doesn't affect myArray, it's just the same thing as

var myArray = [];
var name;

answered Jun 03 '11 at 21:19

brymck

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score 4 · Answer 7 · answered Jun 03 '11 at 21:19

4

It's essentially the instantiation of a second variable name with no value.

answered Jun 03 '11 at 21:19

ShaneBlake

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score 1 · Answer 8 · answered Jan 18 '12 at 16:57

1

The recommended way (clean and short as possible) of writing this kind of code is the following:

var myArray = [],
    name;

answered Jan 18 '12 at 16:57

antonjs

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var myArray =[], name;?

8 Answers8

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