Program logic bugs vs input/environmental errors

[Walter Bright via Digitalmars-d]

On 9/27/2014 6:24 PM, Steven Schveighoffer wrote:
> On 9/27/14 7:15 PM, Walter Bright wrote:
>
>> When I say "They are NOT for debugging programs", I mean they are NOT
>> for debugging programs.
>
> Library code often cannot make that choice.
> The issue with exceptions vs. errors
> is that often you don't know where the input comes from.
>
> e.g.:
>
> auto f = File(someInternalStringThatIsCorrupted) -> error
> auto f = File(argv[1]) -> exception
>
> How does File know what it's target file name came from?

If the app is concerned about invalid filenames as bugs, you should scrub the 
filenames first. I.e. the interface is defined improperly if the code confuses a 
programming bug with input errors.