Feature request: assert expressions should live inside version(assert)

[Tommi]

On Sunday, 7 July 2013 at 12:30:28 UTC, Andrej Mitrovic wrote:
> On 7/7/13, Tommi <tommitissari at hotmail.com> wrote:
>> Sometimes you need to have some extra data to check against in
>> the assert expression. That data isn't needed in release mode
>> when assertions are ignored. Therefore, you put that extra data
>> inside a version(assert). But then those assertions fail to
>> compile in release mode because the symbol lookup for that 
>> extra
>> data fails. For this reason, assert statements should live 
>> inside
>> version(assert) blocks by default.
>
> I've ran into an issue when implementing this feature back in 
> February
> (see the pull request):
>
> http://d.puremagic.com/issues/show_bug.cgi?id=9450
> https://github.com/D-Programming-Language/dmd/pull/1614

Oh, should have searched bugzilla before posting this.

But would it be possible to implement it something like:
During a release build, even though version(assert) blocks are 
compiled out of existence, the compiler would keep a separate 
list of symbols (and other info) of the things declared inside 
those version(assert) blocks. Then, when parsing assert 
expressions, if an undefined symbol is found, the compiler would 
check that separate list of symbols that it has been keeping, and 
if the symbol is found there and use of the symbol is 
syntactically correct, the compiler would just keep on going 
instead of spewing an "unidentified identifier" error.

That way we'd make sure that things like:

assert(this_identifier_doesnt_exist < 12);

...wouldn't compile.