exceptions vs error codes

[Ola Fosheim Grøstad via Digitalmars-d]

On Wednesday, 13 July 2016 at 11:06:54 UTC, ketmar wrote:
> On Wednesday, 13 July 2016 at 11:05:32 UTC, Ola Fosheim Grøstad 
> wrote:
>> Wrong. Just because a language-spec says a compiler writer 
>> does not have to care about a particular type of input does 
>> not mean that the compiler and programmer cannot verify the 
>> data to be valid.
>
> you can't. by definition.

If it is undefined, then there is no definition. Are you trolling 
me?