The question isn't the ability to handle errors, though. You can do it trivially in C too. It's whether or not the design chosen to permit that has benefits t

The question isn't the ability to handle errors, though. You can do it trivially in C too. It's whether or not the design chosen to permit that has benefits that outweigh its costs. And as I said I think the jury is very much still out on that one. Again, we tried to do this with exceptions in the early 90's and whiffed badly. Doing it at the validation/assertion/fuzzing/coverage layer with instrumentation tools turns out to be really effective in practice but the uptake remains really low. Today the mindscape points to Rust's Option as the saviour, which is why I listed it. But as you point out, all these other environments had it much earlier. And... kinda failed. So I'm not hopeful. In-band sentinels like NULLs and error codes are (1) clear and obvious, (2) near-zero-overhead and (3) extremely useful. Everything else falls down on at least one of those requirements.