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digitalmars.D.learn - Looping over Template Types ... possible?

reply james.p.leblanc <james.p.leblanc gmail.com> writes:
Good Evening/Day,

Suppose I have a number of function templates that each take
two types, say S and T.

I would like to exercise my routines over the combinations
of types:

set of all S:  ( double[], float[], Complex!double[], 
Complex!float[])
set of all T:  ( double, float)

Is something along the line of the following sketch possible?

foreach( s in S){
    foreach( t in T){

       foo!(S,T)( T x, S y);
       biz!(S,T)( T x, S y);

    }
}

I have done some searching for hints about this, but I perhaps
my search terms are not very good.

All hint and pointers thankfully received.

Best Regards,
James
Aug 14 2021
parent reply Stefan Koch <uplink.coder googlemail.com> writes:
On Saturday, 14 August 2021 at 20:07:21 UTC, james.p.leblanc 
wrote:

 Good Evening/Day,

 Suppose I have a number of function templates that each take
 two types, say S and T.

 I would like to exercise my routines over the combinations
 of types:

 set of all S:  ( double[], float[], Complex!double[], 
 Complex!float[])
 set of all T:  ( double, float)

 Is something along the line of the following sketch possible?

 foreach( s in S){
    foreach( t in T){

       foo!(S,T)( T x, S y);
       biz!(S,T)( T x, S y);

    }
 }

 I have done some searching for hints about this, but I perhaps
 my search terms are not very good.

 All hint and pointers thankfully received.

 Best Regards,
 James


it is possible

look for `AliasSeq`
in `std.meta`

foreach(T; AliasSeq!(float, double))
{
   ...
}
Aug 14 2021
parent james.p.leblanc <james.p.leblanc gmail.com> writes:
On Saturday, 14 August 2021 at 20:20:01 UTC, Stefan Koch wrote:


 On Saturday, 14 August 2021 at 20:07:21 UTC, james.p.leblanc 
 wrote:


mes

 it is possible

 look for `AliasSeq`
 in `std.meta`

 foreach(T; AliasSeq!(float, double))
 {
   ...
 }


Stefan,

Thanks very much for your help here ... I had not
understood that AliasSeq worked in this manner.

I definitely need read the AliasSeq and try to understand
how to use this.

Best Regards,
James
Aug 14 2021