Forward declaration inside Function block, no error?
schveiguy at gmail.com
Mon Jan 7 19:48:06 UTC 2019
On 1/7/19 12:20 AM, Jonathan M Davis wrote:
> On Sunday, January 6, 2019 11:38:44 AM MST Benjamin Thaut via Digitalmars-d-
> learn wrote:
>> Today I found a bug in my D code.
>> import std.stdio;
>> // Type your code here, or load an example.
>> void grow()
>> void someFunc(bool condition)
>> void grow();
>> I tried to call the grow function, but accidentially copied the
>> return value alongside the function name. I was wondering why
>> this code compiles without errors. the "void grow();" becomes a
>> no-op. In my opinion this could should not compile. Am I missing
>> something here?
> It would actually be useful if you could provide prototypes for extern(C)
> functions that way (similar to how we can have local imports for modules and
> thus avoid affecting the rest of the module), but unfortunately, that
> doesn't currently work (even if the function declaration is marked with
> static). It would also make sense if it allowed you to provide forward
> declarations for nested functions, but that doesn't work either. So, I could
> see uses cases where it would theoretically be useful to be able to declare
> function prototypes inside of a function, but as it stands, AFAIK, it's
> useless. It is arguably a case of "turtles all the way down," but since you
> can't then do anything useful with the function prototype, it's currently
> pretty pointless.
One could use it as a strawman, that's never called, but used for
I tried to use pragma(mangle), but it doesn't seem to work on inner
If I declare the pragma(mangle) outside the function, it works, but that
doesn't help if the function actually needs the outer function context
Allowing forward declarations for nested functions would be nice.
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