I don't understand ... Why you are restricting this behavior to my...?

Every non-initialized variable is not defined.

  DB<1> print $a // "undef"
undef
  DB<2> my $a;print $a // "undef"
undef
  DB<3> our $a;print $a // "undef"
undef
  DB<4> $a=1;print $a // "undef"
1

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UPDATE:

And in most cases accessing an undefined variable will be caught under use warning;.

  DB<1> print $a
 
  DB<2> use warnings; print $a
Use of uninitialized value $a in print at (eval 6)[/usr/share/perl/5.1
+0/perl5db.pl:638] line 2.
..
  DB<3> use warnings; $a=undef;print $a
Use of uninitialized value $a in print at (eval 9)[/usr/share/perl/5.1
+0/perl5db.pl:638] line 2.
..
   DB<4> print $a++
0

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Notable exceptions of this warnings are some altering operators like ".=" and "++" and auto-vivication in hashes and arrays.¹

Cheers Rolf

1) anything else?

... of course boolean context including the defined operator won't throw a warning.

In reply to Re^2: Perl Style: Is initializing variables considered taboo? by LanX
in thread Perl Style: Is initializing variables considered taboo? by ait

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