@ctfeonly

[Mike Franklin]

On Thursday, 7 December 2017 at 01:21:11 UTC, Nicholas Wilson 
wrote:

> I can add this to LDC pretty easily, but does anyone else have 
> a use for this (e.g. shrinking binary sizes for mixin heavy 
> codebases) and would benefit having this as a standard thing?

I've thought about this in the past, but never really pursued it 
much to see if there are already existing facilities in the 
language to accomplish what I want.

I want to enforce that a method is only used at compile time.  
That is I want either the compiler or the linker to throw an 
error if I've accidentally used a function at runtime when I only 
intended it to be used at compile-time.  Also, I want the 
compiler to let me know if my intended-for-compile-time-only 
function cannot be used at compile-time because I mistakenly made 
it dependent on something that is only available at runtime.

That being said, I want D's features to carry their weight.  I 
would first like to prove that facilities don't already exist or 
that existing facilities are too cumbersome to accomplish said 
goal before adding such a feature.

Also, my primary motivation for using D is so I can program 
resource-constrained microcontrollers in a more fun and 
convenient language than C/C++.  I've definitely encountered 
code-size problems in D, but they were mostly due to the 
compiler's unnecessary coupling to the runtime, and the way the 
compiler generated code as the linker couldn't prove that the 
code was dead (Exhibit A: 
https://issues.dlang.org/show_bug.cgi?id=14758).  I don't yet see 
how @ctfeonly would help with that.

Mike