Checked!({short, ushort, byte, ubyte}, Throw): compilation fails

[kdevel]

On Saturday, 18 April 2020 at 08:39:52 UTC, tsbockman wrote:

[...]

>>> You also get a deprecation message, about an integral 
>>> promotion not being performed. I believe the result is 
>>> correct and the warning can be ignored.
>>
>> So the warning is a bug?
>
> The deprecation message is a consequence of a (very annoying) 
> language change made after std.experimental.checkedint was 
> written. It's not really a bug, although someone should 
> probably fix it anyway.

The message suggests using -preview=intpromote. But it produces 
another error:

```minusminus.d
void foo ()
{
    import std.experimental.checkedint;
    Checked!(short) b;
    --b;
}
```

$ dmd -preview=intpromote minusminus.d
[...]/linux/bin64/../../src/phobos/std/experimental/checkedint.d(727): Error: cannot implicitly convert expression onOverflow(this.payload) of type int to short
minusminus.d(5): Error: template instance 
std.experimental.checkedint.Checked!(short, 
Abort).Checked.opUnary!"--" error instantiating

> Anyway, you might want to give my checkedint package on DUB a 
> try, instead:
>
>     https://code.dlang.org/packages/checkedint

Hm.

$ dub test
Generating test runner configuration 'checkedint-test-library' 
for 'library' (library).
Excluding package.d file from test due to 
https://issues.dlang.org/show_bug.cgi?id=11847
Performing "unittest" build using [...]/linux/bin64/dmd for 
x86_64.
checkedint ~master: building configuration 
"checkedint-test-library"...
Linking...
Running ./checkedint-test-library
source/checkedint/package.d(672): [unittest] unittest failure
core.exception.AssertError at source/checkedint/package.d(672): 
unittest failure
----------------
??:? _d_unittestp [0x4c07b5]
source/checkedint/package.d:672 void 
checkedint.__unittest_L654_C5() [0x49959c]
??:? void checkedint.__modtest() [0x4bc4b2]
??:? int 
core.runtime.runModuleUnitTests().__foreachbody2(object.ModuleInfo*) [0x4da1ec]
??:? int object.ModuleInfo.opApply(scope int 
delegate(object.ModuleInfo*)).__lambda2(immutable(object.ModuleInfo*)) [0x4bedb7]
??:? int rt.minfo.moduleinfos_apply(scope int 
delegate(immutable(object.ModuleInfo*))).__foreachbody2(ref 
rt.sections_elf_shared.DSO) [0x4c581f]
??:? int rt.sections_elf_shared.DSO.opApply(scope int 
delegate(ref rt.sections_elf_shared.DSO)) [0x4c5d8c]
??:? int rt.minfo.moduleinfos_apply(scope int 
delegate(immutable(object.ModuleInfo*))) [0x4c57ad]
??:? int object.ModuleInfo.opApply(scope int 
delegate(object.ModuleInfo*)) [0x4bed89]
??:? runModuleUnitTests [0x4da029]
??:? void rt.dmain2._d_run_main2(char[][], ulong, extern (C) int 
function(char[][])*).runAll() [0x4c226c]
??:? void rt.dmain2._d_run_main2(char[][], ulong, extern (C) int 
function(char[][])*).tryExec(scope void delegate()) [0x4c21f8]
??:? _d_run_main2 [0x4c2161]
??:? _d_run_main [0x4c1f1d]
[...]/linux/bin64/../../src/druntime/import/core/internal/entrypoint.d:34 main [0x48c241]
??:? __libc_start_main [0x7ffff700e585]
1/3 unittests FAILED
Program exited with code 1