On 12/06/2014 16:57, simendsjo wrote:
On 06/12/2014 05:46 PM, monarch_dodra wrote:
On Thursday, 12 June 2014 at 15:09:51 UTC, simendsjo wrote:
_ is an often used identifier for "i don't care" in many languages. The
following works:
foreach(_; 0..n)
One issue is that "_" is still an actual identifier, with normal name
collision rules. So that works only once. When you nest your loops,
you'll end up having conflicts, and name your "i don't care variable"
things such as "_", "__", "___", "_1", "_2" etc...
It actually happens quite often I find.
Yeah, not good. Does any sane person use _ as a variable identifier and
then reference it? A breaking change would be a special rule so _ can
never be used and is allowed to shadow.
That might be a more flexible solution, because there is also this usage:
foreach (i, _; range){...}
I wonder if there may be other cases where '_' would be useful.
Potentially, there's also tuple unpacking syntax:
auto (v, _) = myTuple; // throw away second element
Of course - this could break existing code, so it will never happen :)
I think we can break existing code if it's bad code. Using '_' as a
variable name could be considered bad enough to disallow.
