Benchmark of try/catch

[Rainer Deyke]

Daniel Keep wrote:
>> int? value1 = atoi("0");   // 0
>> int? value2 = atoi("#!$"); // null
> 
> Not quite; that assumes null isn't a valid value.  What if the function
> was "getInstance"?

T?? value = getInstance();

> Here's how I understand it to work.  Functions may return a Maybe!(T),
> which is either a T or None (note that None is not null), and is
> implicitly castable to T.

'T??' (aka 'Maybe!(Maybe!(T))') must be a valid type.

In Haskell, a 'Maybe Maybe Integer' can be 'Nothing', 'Just Nothing', or
'Just Just 5'.

In C++, given 'boost::optional<boost::optional<int> > o', you can have
'!o', '!*o', or '**o == 5'.


-- 
Rainer Deyke - rainerd at eldwood.com