Trailing catch on function?

[André Puel via Digitalmars-d]

On Saturday, 12 November 2016 at 12:17:35 UTC, Anonymouse wrote:
> On Wednesday, 9 November 2016 at 09:49:08 UTC, Daniel N wrote:
>> On Tuesday, 8 November 2016 at 16:02:25 UTC, Manu wrote:
>>> scope(failure) doesn't catch... how is that function nothrow?
>>
>> Seems like you overlooked Anonymouse's comment? scope(failure) 
>> catches just fine.
>>
>> scope(failure) return -1;
>> throw new Exception("failure");
>> return 0;
>>
>> This will return -1, with no need for extra indentation.
>
> I understand its convenience, but as long as it also catches 
> Errors I'm not sure this is something you want to do though. 
> You won't be able to differentiate between invalid input and 
> bugs in the code, potentially continuing in an invalid state.
>
> Subsetting failure into a scope(exception) would work, but I'm 
> not sure how the interplay between them would work. Or are 
> Errors so fatal that it should always immediately crash the 
> program, ignored by scope(failure)?

That is how I do it:

     auto csafe(alias f)() nothrow {
         try {
             return f();
         } catch(Throwable e) {
             import core.stdc.stdlib : abort;
             import std.stdio : stderr;
             stderr.writeln("Fatal error.");
             stderr.writeln(e);
             abort();
             assert(false);
         }
     }

And then:

     extern (C) int yada() nothrow {
         return csafe!(() {
             return maythrowFunction();
         });
     }

You might extend the `csafe` function to do some kind of error 
handling, or invoking error callback instead of just aborting the 
execution.