OK, cool. Of course, almost no languages check for totality. Agda is one of the few that does it by default. I think Rust makes you complete all pattern matches too.

However, if you do get a pattern match failure, one of two things is true:

1. You can easily fix it by accounting for all patterns (or adding a default match)

2. Your program model is conceptually broken and you should probably find a new model that accounts for all possible patterns.

Much easier to deal with than a type error :)