Why does this expression return 2 in javaScript?

Question

I would think you might get 0, maybe because the strings are turned to 1's and the - operator causes a subtraction operation to take place?

"1" - - "1";

Thanks in advance!

But isn't 1-(-1) = 1+1 = 2

Leo Lindhorst
– Leo Lindhorst

2015-05-28 15:03:12 +00:00
Commented May 28, 2015 at 15:03 — Leo Lindhorst
– Leo Lindhorst, Commented May 28, 2015 at 15:03

a-d · Accepted Answer · 2015-05-28 15:02:45Z

11

It's how math works

1 - (-1) = 1 + 1

answered May 28, 2015 at 15:02

a-d

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Alex · Accepted Answer · 2017-08-16 10:56:24Z

2

The - casts the string to a number and also acts as a minus sign.

1 - (-1) = 1 + 1 = 2

edited Aug 16, 2017 at 10:56

answered May 28, 2015 at 15:03

Alex

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dimitar veselinov · Accepted Answer · 2015-05-28 15:05:05Z

1

1 - (-1) = 2. I dont see the issue? JavaScript will parse those as integers because of the minus sign, expecting math. It also happens if you multiply a numerical string by 1, aka the poor man's parseInt().

answered May 28, 2015 at 15:05

dimitar veselinov

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