Call different member functions on object sequence with a generic handler function?

[Robert M. Münch]

On 2018-06-29 18:05:00 +0000, Ali ‡ehreli said:

> On 06/29/2018 09:44 AM, Robert M. Münch wrote:
> 
>> So, how can I write a generic handler that does the iteration, where I 
>> can specify which member function to call?
> 
> Passing a lambda or a string mixin:

Hi, that was somehow in my mind but didn't made to get the syntax 
clear... Thanks a lot.

> import std.stdio;
> 
> class C {
>      void A() {
>          writeln(__FUNCTION__);
>      }
> 
>      void B() {
>          writeln(__FUNCTION__);
>      }
> }
> 
> void handler(alias func)(C[] cs) {
>      foreach (c; cs) {
>          func(c);
>      }
> }

Is it possible to make C[] a template type so that I can use different 
classes and lambdas?


> void handler_2(string func)(C[] cs) {
>      foreach (c; cs) {
>          enum expr = "c." ~ func ~ "();";
>          mixin(expr);
>      }
> }

Ok, the "strange" syntax for me is the handler(alias func) or 
handler(string func) ... I'm alway thinkin in lines of a parameter... 
which of course doesn't work.

Looking at the D grammer for functions these things should be the 
FuncDeclaratorSuffix, is this right? And then, which part does this 
fall into?

FuncDeclaratorSuffix:
    Parameters MemberFunctionAttributesopt
    TemplateParameters Parameters MemberFunctionAttributesop



-- 
Robert M. Münch
http://www.saphirion.com
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