Re: nested templates using Complex! with slices, ... confused, I am!
On Monday, 9 August 2021 at 18:44:34 UTC, Paul Backus wrote:
On Monday, 9 August 2021 at 18:35:56 UTC, james.p.leblanc wrote:
```d
T[] foo_temp(Complex!T[])(T x, T y){
auto r = [x, x];
auto i = [y, y];
auto z = [ Complex!T(x, y), Complex!T(x,y) ];
return z;
}
```
void main(){
auto yd = foo_double(1.1, 2.2);
writeln(yd); ...
}
But, no ... I am WRONG! I get the message:
qqq.d(18): Error: identifier expected for template value
parameter
I think what you want is:
```d
Complex!T[] foo_temp(T)(T x, T y) {
auto r = [x, x];
auto i = [y, y];
auto z = [ Complex!T(x, y), Complex!T(x,y) ];
return z;
}
```
This is what I get when I take one of the non-template versions
and replace `float` or `double` with `T`.
H.S & Paul,
Wow, thanks for the quick replies!
It all seems so simple now ... but I just could not see it!
I had been completely (and confidently, unfortunately)
misunderstanding
the syntax of that left most column.
Thanks again,
James
Re: nested templates using Complex! with slices, ... confused, I am!
On Monday, 9 August 2021 at 18:35:56 UTC, james.p.leblanc wrote:
```d
T[] foo_temp(Complex!T[])(T x, T y){
auto r = [x, x];
auto i = [y, y];
auto z = [ Complex!T(x, y), Complex!T(x,y) ];
return z;
}
```
void main(){
auto yd = foo_double(1.1, 2.2);
writeln(yd); ...
}
But, no ... I am WRONG! I get the message:
qqq.d(18): Error: identifier expected for template value
parameter
I think what you want is:
```d
Complex!T[] foo_temp(T)(T x, T y) {
auto r = [x, x];
auto i = [y, y];
auto z = [ Complex!T(x, y), Complex!T(x,y) ];
return z;
}
```
This is what I get when I take one of the non-template versions
and replace `float` or `double` with `T`.
Re: nested templates using Complex! with slices, ... confused, I am!
On Mon, Aug 09, 2021 at 06:35:56PM +, james.p.leblanc via
Digitalmars-d-learn wrote:
[...]
> > **T[] foo_temp(Complex!T[])(T x, T y){
> > auto r = [x, x];
> > auto i = [y, y];
> > auto z = [ Complex!T(x, y), Complex!T(x,y) ];
> > return z;
> > }**
Your syntax is wrong; the declaration should be:
Complex!T[] foo_temp(T)(T x, T y) { ... }
Basically, you're parametrizing on T, and returning an array of a
Complex type built upon T.
T
--
Curiosity kills the cat. Moral: don't be the cat.
nested templates using Complex! with slices, ... confused, I am!
Suppose "foo_double" should return a complex double slice, with
double input args.
Similarly "foo_float" should return a float slice, with float
input args.
I thought it should be easy to parameterize with a template
taking a SINGLE
argument, either a"double" or "float" as follows:
import std.stdio;
import std.complex;
Complex!double[] foo_double(double x, double y){
auto r = [x, x];
auto i = [y, y];
auto z = [ Complex!double(x, y), Complex!double(x,y) ];
return z;
}
Complex!float[] foo_float(float x, float y){
auto r = [x, x];
auto i = [y, y];
auto z = [ Complex!float(x, y), Complex!float(x,y) ];
return z;
}
**T[] foo_temp(Complex!T[])(T x, T y){
auto r = [x, x];
auto i = [y, y];
auto z = [ Complex!T(x, y), Complex!T(x,y) ];
return z;
}**
void main(){
auto yd = foo_double(1.1, 2.2);
writeln(yd); ...
}
But, no ... I am WRONG! I get the message:
qqq.d(18): Error: identifier expected for template value parameter
Nested templates using Complex! really have me confused. How
should I
be thinking about such things in order to understand better?
Best Regards,
James
