DMD 0.166 release

[Chris Nicholson-Sauls]

Ivan Senji wrote:
> Walter Bright wrote:
> 
>> The implicit conversion to delegate just broke too much. Instead, I'm 
>> trying out Tom S.'s suggestion of using a 'lazy' parameter storage class.
>>
>> http://www.digitalmars.com/d/changelog.html
> 
> 
> Hmm, I am afraid I have to admit I'm a little bit puzzled by this lazy 
> thing.
> 
> Let's say we have:
> 
> void dotimes(int count, lazy void exp)
> {
>   for (int i = 0; i < count; i++)
>   {
>     exp();
>   }
> }
> 
> and I can call it like this:
> 
> int x;
> dotimes(5, x++);
> 
> And it works as expected and x end up being 5.
> 
> But shouldn't I also be allowed to pass in a delegate of the appropriate 
> type
> 
> dotimes(5, {writefln(x); x++;});
> 
> A funny thing happens: nothing. The loop in dotimes does get executed 5 
> times but delegate passed in isn't called?
> 
> 

This is because anonymous delegates are themselves expressions, and so your 'exp()' just 
evaluates to the delegate itself -- it does not invoke it.  However, to achieve what you 
were trying to do, just make use of parentheses and the comma operator.  Also, you may 
provide an overload that takes a lazy delegate.  Here is my own test program, which worked 
without issue:

# module lazy1 ;
#
# import std .stdio ;
#
# void dotimes (int count, lazy void exp) {
#   while (count--) exp();
# }
#
# void dotimes (int count, lazy void delegate() exp) {
#   while (count--) exp()();
# }
#
# void main () {
#   int x;
#   dotimes(5, x++);
#   writefln("x is now: ", x);
#
#   int y;
#   dotimes(5, (writefln("[y] ", y), y++));
#   writefln("y is now: ", y);
#
#   int z;
#   dotimes(5, {writefln("[z] ", z); z++;});
#   writefln("z is now: ", z);
# }

-- Chris Nicholson-Sauls