Best practices for type conversion methods

[Sze]

@dimdin

const u = t.from() catch unreachable; // crash on production if Murphy is right

Language Reference: unreachable:

In ReleaseFast and ReleaseSmall mode, the optimizer uses the assumption that unreachable code will never be hit to perform optimizations.

How can it be used for optimizations if you rely on it causing a crash, do you mean, do what ever it wants?

I thought we had come to a consensus that this is a misuse, unless the error is actually impossible. In this doc (error discarding misuse):

Unreachable

unreachable is an assertion that the programmer makes to ensure program correctness and enable compiler optimizations. It is but one among a plethora of other assertions, like casting, indexing and aligning operations, all implemented as safety-checked undefined behavior. For simplification, unreachable’s semantics could be decomposed into several different behaviors depending on evaluation time as well as optimization mode: Hitting unreachable at runtime emits a panic when compiled in Debug …