mixin under -betterC

[Basile B.]

On Thursday, 23 November 2023 at 16:33:52 UTC, DLearner wrote:
> Code below is intended to test simple mixin with lambda 
> function under -betterC.
> Works with full-D, but fails with 'needs GC' errors under 
> -betterC.
>
> Why is this so, bearing in mind the concatenations are executed 
> at
> compile, not run, time?
> ```
> // Test harness
>
>    extern(C) void main() {
>       import core.stdc.stdio : printf;
>       import testmod;
>
>       bool FirstVarGreater;
>       int Var_A = 4;
>       int Var_B = 3;
>
>
>       FirstVarGreater = mixin(mxnTest("Var_A", "Var_B"));
>       if (FirstVarGreater) {
>             printf("First Var is Greater\n");
>       } else {
>             printf("First Var is not Greater\n");
>       }
>    }
>
>
> // testmod
>
> string mxnTest(string strVar1, string strVar2) {
>    return `(int Var1, int Var2) {
>       if (Var1 > Var2) {
>          return true;
>       } else {
>          return false;
>       }
>    }(` ~ strVar1 ~ `,` ~ strVar2 ~ `)`;
> }
> ```

You've been explained the reason why that does not work, note 
however that it's not hopeless see

- 
https://forum.dlang.org/thread/ahqnylrdftmmvtyvompr@forum.dlang.org
- https://github.com/dlang/dmd/pull/15636

unfortunately the PR is stalled since two months.