• terranium <spam here.lot> May 07 2008
• BCS <BCS pathlink.com> May 07 2008

terranium <spam here.lot> writes:

downs Wrote:

 As such, an exception (which is reserved, appropriately, for *exceptional*
events), is totally the wrong approach to use.
 



 Note that with the current behavior, you can incur the runtime speed loss of
throwing an exception if you _want_ to, by using the above templated wrapper,
but if throwing an exception were the only possibility, you couldn't possibly
get that speed back.
 

BCS <BCS pathlink.com> writes:

terranium wrote:
 downs Wrote:
 
 
As such, an exception (which is reserved, appropriately, for *exceptional*
events), is totally the wrong approach to use.


 Yes, function received wrong input, this is normal, if we want, we throw
exception, if we want, we ignore it.
 


The point is that offtent a failed cast is not an indecation of an 
error. For instance code like this

class A {}
class B1 : A {}
class B2 : A {}

void foo(A a)
{
   if(auto b = cast(B1)a) {}
   else if(auto b = cast(B2)a) {}
   else {}
}