Re: Strings concatenated at compile time?

[bearophile via Digitalmars-d-learn]

Jonathan M Davis:


If you want it to be guaranteed, you'd do something like

template foo(string s)
{
enum foo = s ~ " betty";
}


A more general solution is to wrap the concatenation with a call 
to:


alias ctEval(alias expr) = expr;

Use:

string bar() { return ctEval!(s ~ " betty"); }

Bye,
bearophile

Re: Strings concatenated at compile time?

[Jonathan M Davis via Digitalmars-d-learn]

On Thu, 01 May 2014 11:12:41 +
anonymous via Digitalmars-d-learn 
wrote:

> On Thursday, 1 May 2014 at 10:42:36 UTC, Unwise wrote:
> > In the following example from the documentation, are strings 
> > concatenated at compile time?
> >
> > template foo(string s) {
> >   string bar() { return s ~ " betty"; }
> > }
> >
> > void main() {
> >   writefln("%s", foo!("hello").bar()); // prints: hello betty
> > }
> 
> I guess it's not guaranteed, but constant folding should take 
> care of it, yes.

If you want it to be guaranteed, you'd do something like

template foo(string s)
{
enum foo = s ~ " betty";
}

void main()
{
writeln(foo!"hello");
}

I would hope that the optimizer would have optimized out the
concatenation in your example though.

- Jonathan M Davis

Re: Strings concatenated at compile time?

[anonymous via Digitalmars-d-learn]

On Thursday, 1 May 2014 at 10:42:36 UTC, Unwise wrote:
In the following example from the documentation, are strings 
concatenated at compile time?


template foo(string s) {
  string bar() { return s ~ " betty"; }
}

void main() {
  writefln("%s", foo!("hello").bar()); // prints: hello betty
}


I guess it's not guaranteed, but constant folding should take 
care of it, yes.

Strings concatenated at compile time?

[Unwise via Digitalmars-d-learn]

In the following example from the documentation, are strings 
concatenated at compile time?


template foo(string s) {
  string bar() { return s ~ " betty"; }
}

void main() {
  writefln("%s", foo!("hello").bar()); // prints: hello betty
}