David Storrs <[EMAIL PROTECTED]> writes:
> I image we've all written logging code that looks something like this
> (Perl5 syntax):
>
> sub foo {
> my ($x,$y) = @_;
> note("Entering frobnitz(). params: '$x', '$y'");
> ...
> }
>
> This, of course, throws an 'uninitialized value in concatenation or
> string' warning when your test suite does this:
>
> is( foo(undef, undef), undef, "foo(undef, undef) gives undef" );
>
> In a testing environment, I don't want to see this warning.
>
> In a
> production environment, I do. Furthermore, when I want it gone, I
> want it gone from every instance of C<note>, without having to change
> something in every location. I suppose I could change all my logging
> calls to look like this:
>
> {
> if ( $DEBUG ) { no warnings 'uninitialized'; note("...."); }
> else { note("...."); }
> }
>
> But that's really ugly, takes up a lot of space, is confusing, and is
> redundant.
>
> How would I best solve this problem in Perl6?
Write an appropriate macro:
warns(is( foo(undef, undef), undef, "foo(undef, undef) gives undef"),
"uninitialized value in concatenation or string");
That way you get to ensure that the warning gets thrown correctly if undef is
passed, but you don't get the warning mucking up your test output.
