Elegant breaking from nested loops

[Blacksmoke16]

Throw and catch

So, most of all familiar with throw and catch thing in Ruby. It’s sometimes useful to be able to break away from a deep-leveled stack. And raising a error is quite expensive. Why isn’t it in the language yet?

Also related: throw and catch with `SkipMacroException` · Issue #11658 · crystal-lang/crystal · GitHub.