I found this weird syntax:
int a = {1,};
And it works in all the compilers I've tried. How does it compile?
EDIT: I thought that scalar initializers can only have one element in it, spawning my question. Sorry for all the trouble.
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3Please do everyone a favor, and don't let the author of that line get away unpunished. Call him/her to the water cooler, roll up a newspaper, whack him/her and say "No! Bad! Bad programmer!" – DanielKO Dec 01 '14 at 04:11
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@DanielKO Of what line? – user4309946 Dec 01 '14 at 04:18
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1The line you posted, `int a = {1,};`, you said you found it. It's a tongue-in-cheek way to say please don't ever write code like this, unless you are creating a submission for the IOCCC. – DanielKO Dec 01 '14 at 04:21
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As stated by Matt McNab in comments, the syntax of a braced initialized list is the same regardless of whether you are using it to initialize a scalar or anything else.
C++11 §5.17 states
A braced-init-list may appear on the right-hand side of
- an assignment to a scalar, in which case the initializer list shall have at most a single element.
The definition of braced-init-list is (from §8.5):
braced-init-list:
{ initializer-list ,opt }
{ }
where the 'opt' means that the trailing comma is optional.
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Yes I know that. It's the only one I have access to however. I updated somewhat to clarify that. – harmic Dec 01 '14 at 01:16
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5+++1 Great answer to _this_ question not some other question. – Lightness Races in Orbit Dec 01 '14 at 01:16
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@harmic I know you know that, I just found it weird how you put "ISO" for no discernable reason. – Dec 01 '14 at 01:21
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1It's really usefull when initialiser/enums are on multiple lines. If you finish your list with comma and add a parameter, the diff is only on the new parameter line and not on the last two. – ColdCat Dec 01 '14 at 08:49