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digitalmars.D.learn - lambda template literals?

reply bearophile <bearophileHUGS lycos.com> writes:
Is code vaguely like this meaningful and useful?


void main() {
    alias (x => x ^^ 2) sqrTemplate;
}


Bye,
bearophile
Jan 17 2012
parent reply Timon Gehr <timon.gehr gmx.ch> writes:
On 01/18/2012 01:35 AM, bearophile wrote:

 Is code vaguely like this meaningful and useful?


 void main() {
      alias (x =>  x ^^ 2) sqrTemplate;
 }


 Bye,
 bearophile



Yes. The fact that your particular example does not work is a mere 
syntactic issue.
This works:

template ID(alias a){alias a ID;}
void main(){
     alias ID!(x => x ^^ 2) sqrTemplate;
}
Jan 17 2012
next sibling parent reply bearophile <bearophileHUGS lycos.com> writes:
Timon Gehr:


 Yes. The fact that your particular example does not work is a mere 
 syntactic issue.
 This works:
 
 template ID(alias a){alias a ID;}
 void main(){
      alias ID!(x => x ^^ 2) sqrTemplate;
 }



Thank you Timon, you are often good :-)
I'll add it as enhancement request.

Bye,
bearophile
Jan 17 2012
parent bearophile <bearophileHUGS lycos.com> writes:
Philippe Sigaud:


 This limitation (not being able to alias a lambda) is quite irksome.
 If you do an enhancement request, could you also add one for:
 
 alias __traits(whatever, whatever) some Result;
 
 Right now, the alias grammar doesn't allow this and I find this
 limitation jarring.



It's better to add it yourself:
http://d.puremagic.com/issues/show_bug.cgi?id=7308

Bye,
bearophile
Jan 18 2012
prev sibling parent Philippe Sigaud <philippe.sigaud gmail.com> writes:
On Wed, Jan 18, 2012 at 02:06, bearophile <bearophileHUGS lycos.com> wrote:


 template ID(alias a){alias a ID;}
 void main(){
 =C2=A0 =C2=A0 =C2=A0alias ID!(x =3D> x ^^ 2) sqrTemplate;
 }



 Thank you Timon, you are often good :-)
 I'll add it as enhancement request.



This limitation (not being able to alias a lambda) is quite irksome.
If you do an enhancement request, could you also add one for:

alias __traits(whatever, whatever) some Result;

Right now, the alias grammar doesn't allow this and I find this
limitation jarring.
Jan 18 2012