This is an interesting coincidence, I was just about to post a meditation regarding a problem that I've just this minute figured out.
use strict;
use warnings;
my %const;
#Initialise params
$const{pid} = 1;
$const{pidwithzeros} = '0' x (10 - length $const{pid}) . $const{pi
+d },
#Check params
die "Invalid PID $const{pid}\n" if not $const{pid} =~ /^[0-9]+$/;
#Various lines of code removed
print $const{pidwithzeros}, "\n";
I was getting an "uninitialized value in print" warning on the final line. The mistake is obviously that the comma at the end of line 8 should be a semi-colon but for the life of me I couldn't see it. To try and find out what was going on I changed the code to the following but this only deepened my confusion:
use strict;
use warnings;
my %const;
#Initialise params
$const{pid} = 1;
$const{pidwithzeros} = '0' x (10 - length $const{pid}) . $const{pi
+d },
#Debug line
print $const{pidwithzeros}, "\n";
#Check params
die "Invalid PID $const{pid}\n" if not $const{pid} =~ /^[0-9]+$/;
#Various lines of code removed
print $const{pidwithzeros}, "\n";
With the debug line in the code worked as expected. Without and the error would appear. Confusion reigned. Half an hour of thinking I was going bonkers later and as I was preparing a post to SoPW, I saw it.
Hey hum.
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