Perfectly reasonable question. Basically, you can consider it a NOP if there's no observable side-effect. Obviously, stdout has a particular purpose and you w

Perfectly reasonable question. Basically, you can consider it a NOP if there's no observable side-effect. Obviously, stdout has a particular purpose and you wouldn't just disable the side-effect for one use case, but you could imagine having some pseudo console for the purpose of emitting debug messages which is considered a non-effect in your language (provided you can't read from it and reify the text back into values). In .NET for example, you can use `Debug.Write` and `Trace.Write` for emitting debug messages, and these lines are erased from the release version of the binary. You can mark any void-returning function with the `[Conditional("DEBUG")]` attribute and have calls to it erased because the DEBUG symbol is not defined in release versions. IMO, this should be standard in all languages - in languages with effects even moreso because we don't want to pass around an effect if our only use for it is debug or trace messages.