Foreach Closures?

[Timon Gehr]

On 04/10/2012 11:33 AM, Andrej Mitrovic wrote:
> On 4/9/12, Kevin Cox<kevincox.ca at gmail.com>  wrote:
>> The
>> reason I aski is because if you have a return statement inside a foreach it
>> returns from the outside function not the "closure".
>
> I don't like this subtle thing. For example let's say a newbie were to
> implement a function called "isDirEmpty". The first hint is to try to
> walk the directory iteratively and return as soon as there's a match,
> e.g.:
>
> bool isEmptyDir(string path)
> {
>      foreach (_; dirEntries(path, SpanMode.shallow))
>          return false;
>
>      return true;
> }
>
> isEmptyDir never returns false.

Yes it does.

> All that false statement does is break
> out of the foreach loop.
>

??? No, it returns false from isEmptyDir, unless the opApply 
implementation abuses operator overloading.