On Wednesday, 27 March 2013 at 17:23:01 UTC, Timon Gehr wrote:
I strongly disagree. What would be an example of the problems
you are apparently experiencing?
T foo(alias fallback)() {
// Do some processing return the result. If an error occurs
use fallback mechanism.
}
Reasonable thing to do as fallback is to try another method
workaround the error, throw, whatever.
The problem is that the fallback type inference makes it painful
to work with, especially if fallback is a template itself.
For instance, in SDC, you can parse ambiguous things as follow :
parseTypeOrExpression!((parsed) {
static if(is(typeof(parsed) : Expression)) {
// Do something
} else {
throw SomeException();
}
})(tokenRange);
This is bound to fail. When a function never return, it make no
sens to force a type on it and the magic subtype typeof(null)
should be used (as typeof(null) can cast to anything, it is valid
to call the function in any condition).
