foo!(bar) ==> foo{bar}

[KennyTM~]

Andrei Alexandrescu wrote:
> KennyTM~ wrote:
>> Andrei Alexandrescu wrote:
>>> Alexander Pánek wrote:
>>>> Steven Schveighoffer wrote:
>>>>> "Alexander Pánek" wrote
>>>>>> Steven Schveighoffer wrote:
>>>>>>> Everything runs together, looks like one big word.  I think we 
>>>>>>> need a full height character to represent template brackets, 
>>>>>>> something with a lot of whitespace to separate it from the other 
>>>>>>> characters.
>>>>>> Heh... sounds like !() to me! ;)
>>>>>
>>>>> *gasp*  That's perfect!  I say we go with it ;)
>>>>
>>>> Has my vote, for sure!
>>>
>>> One possibility to make progress would be to keep !( but allow 
>>> omitting the parens when only one argument is being passed. That way 
>>> many instantiations will be helped. For example, in wake of the 
>>> impending demise of complex built-ins:
>>>
>>> Complex!double alpha;
>>> Complex!float[] data;
>>>
>>> That way, again, we leverage the fact that an extra symbol is needed 
>>> instead of compulsively requiring it in addition of the parens.
>>>
>>> One nice thing about this change is that it keeps all code as it is, 
>>> just lifts one restriction.
>>>
>>> How about that?
>>>
>>>
>>> Andrei
>>
>> vote++ for this.
>>
>> But how do templates with no arguments be called? Is “T!” valid?
> 
> Offhand, that looks like it can't work, but haven't we all been wrong 
> before? :o)
> 

I guess no. And a template having no parameters isn't really that common 
I guess? I haven't encountered one as least. I also realized if ! is a 
binary operator then it shouldn't act as a postfix operator also.

(Or maybe reserve the postfix operator ! for factorial, i.e. 5! == 120 
/joke)

>> If so, can these ambiguity be solved first? These are minor cases, 
>> though.
>>
>> (1) opCall strikes again!
>>
>> class T(int n = 6) {
>>         static int opCall (int z) {
>>                 writefln(z);
>>         return z;
>>         }
>>     static char init;
>> }
>>
>> void main() {
>>     auto x = T!(4).init;
>> }
> 
> This is not an opCall issue. A template can alias itself to anything. 
> Consider:
> 
> template A(T = int)
> {
>     alias foo A; // say foo is a function
> }
> 
>> (2) !is
>>
>> template T() {
>>     enum T = 3;
>> }
>>
>> void main () {
>>     writeln(T!is 3);
>> }
> 
> This is not a problem because "is" is a keyword.
> 
> 
> Andrei