How to implement filterMap

[Alexandru Ermicioi]

On Sunday, 31 December 2023 at 09:47:27 UTC, Siarhei Siamashka 
wrote:
> Also take a look at the `c` array. The handling of arithmetic 
> overflows is a safety problem of the D language design. Certain 
> types of input may cause overflows, which result in producing 
> bogus data as a result of running your program and are very 
> difficult to troubleshoot. The use of the GDC's `-ftrapv` 
> option surely helps in troubleshooting such cases, but some 
> software or D libraries may intentionally rely on the D's 
> arithmetic wraparound feature.

`CheckedInt` should be another solution for overflows, if you 
really need it to throw exceptions, on overflow errors.