A co-worker just sent me a snippet of code and asked why it behaved like it does, and I can't really figure out why it does, can someone explain this behavior to me?
perl -w -e 'use strict;my $t;
if (scalar (keys %{$t->{r}}))
{print "There are keys\n";}
print "t->{r} = $t->{r}\n"; 
'
t->{r} = HASH(0x80fbc50)

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If I omit the if and only does:
 perl -w -e 'use strict;my $t = undef;
my %p = %{$t->{r}};
print "t->{r} = $t->{r}
";
'

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I get this error:
Can't use an undefined value as a HASH reference at -e line 2.
Why is it behaving like this? I can't see why $t->{r} gets defined in the first snippet

In reply to does if(%{$ptr->{key}}) define? by jmo

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