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Answer 1

+6 A:

The leading zero is probably making it think the number is octal.

UPDATE: Thanks to @Paul Dixon for jogging my mind awake somewhat this morning. 01004 is a literal, so no amount of after-the-fact parsing, i.e., parseInt, is going to update the base of the number. You need to either strip the leading 0 in your code to make it 1004 (the easiest solution), or put quotes around the literal to make it a string before sending it to parseInt (which is more work for no reason I can see).

Hank Gay 2009-01-12 09:30:28

Thanks for the quick reply!I tried parseInt on the number, but still I am getting 516 in the alert box. Should I convert 01004 to numeric, even before I pass this to JavaScript function!?

Veera 2009-01-12 09:32:13

The funny part is that if I put an explicit parseInt(num, 10) in the body of `test`, it is still broken. If I then wrap 01004 in quotation marks, e.g., test('01004'), it works.

Hank Gay 2009-01-12 09:40:03

Please accept Paul Dixon's answer, since it's much more coherent.

Hank Gay 2009-01-12 09:56:50

Answer 2

A:

Quote the number -> '01004'

EDIT: I see parseInt('01004', 10) works fine... I really don't know why parseInt(01004, 10) doesn't

EDIT2: Ok, thanks to Paul Dixon

tanathos 2009-01-12 09:38:48

This does indeed fix it, but I can't figure out why.

Hank Gay 2009-01-12 09:40:47

This only works because it's no longer a number, it's a string... From the original question I'm assuming a number is required.

J-P 2009-01-12 09:42:17

it turns it from a numeric literal expressed in octal to a string literal

Paul Dixon 2009-01-12 09:42:19

I supposed he wants to pass a string: 01004 isn't a number, 1004 is.

tanathos 2009-01-12 09:44:26

Yes, but why is parseInt with an explicit base of 10 failing? alert(parseInt(01004, 10)) -> 516

Hank Gay 2009-01-12 09:45:32

01004 is just another way of writing 516, so alert(parseInt(01004, 10)) is equivalent to alert(parseInt(516, 10))

Paul Dixon 2009-01-12 09:49:06

eheh, I think Hank has the right, maybe the presence of the first zero pull the javascript to evaluate the number as an octal, and it bypass the function. But with alert(parseInt('01004', 10)), it works right

tanathos 2009-01-12 09:49:27

Gah! Of course it is. This is what happens when you answer before coffee: you convince yourself that a number literal will get parsed as a string literal. Thanks for putting up with the density.

Hank Gay 2009-01-12 09:51:25

Answer 3

+10 A:

A numeric literal that starts with a zero is interpreted as octal, so writing 01004 is exactly the same as writing 516.

Some other answers suggesting using parseInt inside the function to convert the octal value to decimal.

This wont help, as the numeric value 516 is passed to the function. If you ask parseInt to give you a base 10 interpretation back, you'll get 516!

The way to fix this is either to lose the leading zero, or if the zero is required, make it a string literal rather than a numeric, and use parseInt(num, 10) inside the function.

Paul Dixon 2009-01-12 09:46:56

Thanks Paul! it worked!!

Veera 2009-01-12 10:16:36

Answer 4

+1 A:

Congratulations, you are the one millionth customer to get tripped up by octal literals in a language descended from B (and hence C).

Your prize is to lead the pitchfork parade outside Ken Thompson's house.

bobince 2009-01-12 11:31:06

You never forget your first octal literal cockup :)

Paul Dixon 2009-01-12 12:44:56

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