## Summary `Control.Exception.assert` allows the user to do assertions in development which disappear when compiled with optimizations enabled. However, `Control.Exception.assert` always throws an `AssertFailed` exception. There are cases in which a user might want to do other kinds of assertions: Either throwing a different kind of exception, or maybe different logic (that is not related to exceptions) all-together. ## Proposed solution A very simple and flexible way to provide the user with this ability, is to expose whether the `fignore-asserts` flag is enabled (either directly or by using `-O1`/`-O2` without also specifying `-fno-ignore-asserts`) as the CPP macro `__GLASGOW_HASKELL_ASSERTS_IGNORED__`. This particular design was chosen in collaboration with @bgamari.