Redirecting thread to language because I do agree that this is no longer a
matter of a bug.
On Fri, Sep 18, 2009 at 9:28 AM, Moritz Lenz via RT <
perl6-bugs-follo...@perl.org> wrote:
> On Thu Sep 17 08:53:59 2009, ajs wrote:
> > This code behaves as expected, matching 2 or 3 in only one out of the
> three
> > cases:
>
> You say yourself that it behaves as expected, I don't see any bug.
>
>
Yeah, I dropped a comma. That should have been "This code behaves as
expected, matching 2 or 3, in only one out of the three cases.
> The case 2..3 (Range) is pretty clear. S03/Smart Matching/ says about
> Arrays:
>
> Any Array lists are comparable @$_ «===» X
>
> so it tries to interpret the LHS as a List and checks for element-wise
> identity => False
>
I think I see where you're going, here: that ranges are explicitly called
out in the spec for given (I haven't double-checked that, but I seem to
recall that that's right).
The problem is that we now have this rule (which is what caught me, here and
made me think this was a bug):
2,3 constructs a list. 2..3 also constructs a list, unless it's in a
given/when condition in which case it's just a range.
That seems confusing. Is there any value at all in comparing a scalar to a
list for identity by default? Why wouldn't we apply any() implicitly and get
free consistency with the behavior of lists constructed with ..?
Original code:
my $a = 2;
print "Test 1 (anon array): ";
given $a {
when [2,3] { say "Good" }
default { say "Bad" }
}
print "Test 2 (..): ";
given $a {
when 2..3 { say "Good" }
default { say "Bad" }
}
print "Test 3 (bare ,): ";
given $a {
when 2,3 { say "Good" }
default { say "Bad" }
}
