Today I head to localize an "uninitialized value" warning in a fairly big here doc with many interpolated variables.

Surprisingly Perl didn't tell me which variable was causing the trouble.

A closer investigation revealed that accessing hash entries via a dereference omitted the details.

Here a test in 5.22 

 
$ perl -wE 'my $x={};my %h; say "plain $h{new} deref $x->{new}"'
Use of uninitialized value $h{"new"} in concatenation (.) or string at
+ -e line 1.
Use of uninitialized value in concatenation (.) or string at -e line 1
+.
plain  deref

[download]

is it a bug or is there a reason why Perl can't localize $x?

FWIW I tested 5.8.9 and back then no hints at all where given:

$ perlbrew use perl-5.8.9
$ perl -we 'my $x={};my %h; print "plain $h{new} deref $x->{new}"'
Use of uninitialized value in concatenation (.) or string at -e line 1
+.
Use of uninitialized value in concatenation (.) or string at -e line 1
+.

[download]

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to BUG in warnings uninitialized for derefed hashes? by LanX

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