Re: template mixins vs alias
In your case I would guess with -O -release -inline it would generate
assambly with same (similar) speed.
But in this case it would be different:
mixin template Test()
{
int returnInit() { return int.init; }
}
int returnInitImpl() { return int.init; }
class A
{
mixin Test!(); // add virtual method
}
class B
{
alias returnInit = returnInitImpl;
}
import std.stdio;
void main()
{
auto a = new A();
auto b = new B();
a.returnInit().writeln;
b.returnInit().writeln;
}
Dne 22.2.2016 v 15:12 Andrea Fontana via Digitalmars-d-learn napsal(a):
On Monday, 22 February 2016 at 13:56:19 UTC, anonymous wrote:
On Monday, 22 February 2016 at 13:35:10 UTC, Andrea Fontana wrote:
Check this code:
http://dpaste.dzfl.pl/fcf876acbbdc
Structs A and B do the same things, in different way.
Is there any difference/limitation between those?
Andrea
The mixin variant generates a method. That means, you can reference
members of the struct in the function.
Of course, but that's not the case.
What's nicer about the alias version is that you see what symbol is
being generated. It's obvious that `alias returnInit =
returnInitImpl!int;` creates a symbol "returnInit". In the mixin
variant, you have to read the template's source to see that.
I wonder whether one version generates faster assembly or not.
Re: template mixins vs alias
On Monday, 22 February 2016 at 13:56:19 UTC, anonymous wrote: On Monday, 22 February 2016 at 13:35:10 UTC, Andrea Fontana wrote: Check this code: http://dpaste.dzfl.pl/fcf876acbbdc Structs A and B do the same things, in different way. Is there any difference/limitation between those? Andrea The mixin variant generates a method. That means, you can reference members of the struct in the function. Of course, but that's not the case. What's nicer about the alias version is that you see what symbol is being generated. It's obvious that `alias returnInit = returnInitImpl!int;` creates a symbol "returnInit". In the mixin variant, you have to read the template's source to see that. I wonder whether one version generates faster assembly or not.
Re: template mixins vs alias
On Monday, 22 February 2016 at 13:35:10 UTC, Andrea Fontana wrote:
Check this code:
http://dpaste.dzfl.pl/fcf876acbbdc
Structs A and B do the same things, in different way.
Is there any difference/limitation between those?
Andrea
The mixin variant generates a method. That means, you can
reference members of the struct in the function.
Silly example:
mixin template Test(T)
{
auto returnX() { return x; }
}
struct A
{
int x;
mixin Test!int;
}
With the alias variant you get an alias to a free function, not a
method. So you couldn't reference x like above.
What's nicer about the alias version is that you see what symbol
is being generated. It's obvious that `alias returnInit =
returnInitImpl!int;` creates a symbol "returnInit". In the mixin
variant, you have to read the template's source to see that.
template mixins vs alias
Check this code: http://dpaste.dzfl.pl/fcf876acbbdc Structs A and B do the same things, in different way. Is there any difference/limitation between those? Andrea
