The language spec says:

"The compiler may optionally not evaluate assert expressions at all."

In practice, this means that it depends on compiler flags. For DMD, assert expressions are ignored in -release.

Sometimes, I want to do things only when asserts are being compiled, for example:

version(release) {} else import std.format;
assert(x == 0, format("x is %d, not 0", x));


I have two problems with this:

1. It's ugly to use the version... else syntax.
2. It's tied to the fact that DMD doesn't compile asserts in release.

What I would prefer:

version(assert) import std.format;


Of course, version(assert) is compiled when asserts are compiled.

This makes the intent clear, and removes coupling with particular compiler options.

Thoughts?

On 02-09-2012 13:39, Peter Alexander wrote:
> The language spec says:
>
> "The compiler may optionally not evaluate assert expressions at all."
>
> In practice, this means that it depends on compiler flags. For DMD,
> assert expressions are ignored in -release.
>
> Sometimes, I want to do things only when asserts are being compiled, for
> example:
>
> version(release) {} else import std.format;
> assert(x == 0, format("x is %d, not 0", x));
>
>
> I have two problems with this:
>
> 1. It's ugly to use the version... else syntax.
> 2. It's tied to the fact that DMD doesn't compile asserts in release.
>
> What I would prefer:
>
> version(assert) import std.format;
>
>
> Of course, version(assert) is compiled when asserts are compiled.
>
> This makes the intent clear, and removes coupling with particular
> compiler options.
>
> Thoughts?

(Sorry, managed to reply directly via email with the previous message.)

Yes: https://github.com/D-Programming-Language/dmd/pull/1099

(If that's accepted, I'll send patches to GDC and LDC as well.)

-- 
Alex Rønne Petersen
alex@lycus.org
http://lycus.org

On Sunday, 2 September 2012 at 12:49:39 UTC, Alex Rønne Petersen
wrote:
> Yes: https://github.com/D-Programming-Language/dmd/pull/1099
>
> (If that's accepted, I'll send patches to GDC and LDC as well.)

Thanks, was going to do it myself if there was interest, but
you've saved me the effort :-)

Also, I have now realised that version(release) doesn't work...