Re: [Caml-list] Uncaught exceptions in function type.

["Daniel Bünzli" <daniel.buenzli@erratique.ch>]

Le mardi, 27 mai 2014 à 11:25, Nicolas Boulay a écrit :

> > Because that would be utterly annoying. You need to make the following distinctions:
>  
> Yes it could be annoying, but very high quality software become much harder to write. Refactoring is harder. Missing exception handler are harder to find.

That’s non sense. What would the programmer do if Array.create wouldn’t raise in case of invalid argument 99.9999999% of the code would read like this:  

let a = match Array.create n with  
| None -> assert false  
| Some a -> a  
in

You solved absolutely nothing by having an option type here. But you did manage to be annoying.
  
>  
> > * Exceptional errors, for errors that the programmer is unlikely to handle at all (e.g. out of memory). For that raise a custom exception. This should occur very rarely, you are unlikely to ever define one such exception.
>  
> That means intensive testing to be sur to avoid such failure for normal user input. For most long running programme (server, gui), that's could a problem.
>  
> For example, an undo/redo use lot of memory after some copy/paste on big data, then the save command have not enough memory to work, and the file are troncated. That's not acceptable, and can be see only with big data, after few high level command run.
That is certainly not something you want to solve by handling exceptions but by making sure/designing your program is able to function under a given fixed memory budget (if only to be able to test the error condition).  

Best,

Daniel