For the most part, that is true, you should always use "my". There are a few cases where local is better: 
local *HANDLE;
local $SIG{ALRM} = 'ignore';

my $x = 2;
################# UPDATE #######################
## Without removing my mistake above, so that
## anybody reading this node will note how
## silly (see Dominus's generous -cough- reply)
## I was (and I was silly to post code that I
## would never actually use and hadn't tested
## in a negative response to an almost saintly monk).
##
## The reason the code failed is because
## I need to do something like:
## use vars qw($x);
##  OR
## $main::x;
## Otherwise, local will fail (as per ctl's reponse)
## because it doesn't have access to "my"ed variables.
## It won't fail on the grounds that you shouldn't use
## local.
##
## Dominus didn't answer the response.
## There are still times when you need to use local
## (and saying only use IO::Handle or Symbol::gensym() or
## don't use SIG's is not an appropriate answer -- 
## sometimes we have no choice but to use FILEHANDLES
## and SIG's)
##
## Meanwhile maybe I should post a meditation about 
## answering with answers and not predispositions.
################# UPDATE #######################
sub A {
  local $x = 3;
  &B;
}
sub B{ $x }

print &A; #prints 3 not 2

[download]


So, unless you need something like the above (and understand why), you really should use "my" (or fully qualify the variable). my @a=qw(random brilliant braindead); print $a[rand(@a)];

In reply to Re: Re: I need a simple explantion of the difference between my() and local() by Rhandom
in thread I need a simple explantion of the difference between my() and local() by Jemts

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