On Mon, Sep 29, 2014 at 8:13 AM, Steven Schveighoffer via Digitalmars-d < digitalmars-d@puremagic.com> wrote:
> My entire point is, it doesn't matter what is expected or what is treated > as "correct." what matters is where the input CAME from. To a library > function, it has no idea. There is no extra type info saying "this > parameter comes from user input." >From the method's view, parameters passed in are user input. Full stop. One thing that seems to be talked around a bit here is the separation/encapsulation of things. It is perfectly fine, and expected, for a library method to throw exceptions on bad input to the method - even if this input turns out to be a programming bug elsewhere. From the standpoint of the method, it does not know (and does not care) where the thing ultimately came from - all it knows is that it is input here, and it is wrong. If you call a method with bad input, and fail to catch the resulting exception, then _that_ is a bug, not the method throwing. It may be perfectly recoverable to ignore/retry/whatever, or it may be a symptom of something that should abort the program. But the method throwing does not know or care.
