Which is why you don't throw errors but return a result type such as Rust's Result, Haskell's Either, or C++'s upcoming std::expected :) On the other hand, non

Which is why you don't throw errors but return a result type such as Rust's Result, Haskell's Either, or C++'s upcoming std::expected :) On the other hand, non-atomically asking for permission first in any concurrent (or re-entrant!) context is not just an antipattern but simply wrong and always a possible race condition. It is impossible to write a routine that tries to open a file and is statically guaranteed to succeed.