On 21/11/2010 09:56, addie wrote:
I have been fighting with this problem for over a week now he really
aggravating thing is that I had it working for over a year without
problem. have tried everything I can imagine. I've cut the code down
to a toy version to isolate the problem and it is no help. For the
sake of this issue let's say that I am trying to populate a hash from
a space delimited file and then, using a list of keys from another
file to iterate over and access each of the values for further use in
the program.
#!/usr/bin/
perl
\
use strict;
use warnings;
my %hash = ();
my $key = '';
open ACCESSIONS, "fix.txt" or die "Can't open fix.txt: $!\n";
while (my $locus_line =<ACCESSIONS>){
#This is supposed to populate
%hash.
%hash = split(/\s/, $locus_line);
foreach my $k (keys %hash) {
# print "$k $accesshash{$k}
\n";
}
}
close ACCESSIONS;
open INKEYS, "in.txt" or die "Can't open in.txt: $!\n";
while (my $x =<INKEYS>){
#var is the key whose value I will want to grab for use later in the
program.
$key = $x;
chomp($key);
#Some debug lines to check the output by Alex
Batko
print "Value EXISTS, but may be undefined.\n" if exists
$hash{$key};
print "Value is DEFINED, but may be false.\n" if defined
$hash{$key};
print "Value is TRUE at hash key $var.\n" if
$hash{$key};
print "$key ";
print $hash{$var};
print "\n";
}
print "\n" . $hash{$var};
print "\n";
close INKEYS;
This seems to populate the hash just fine. When trying to access those
same hash elements, however, I get various flavors of "Use of
uninitialized value in ...." I have even tried to use the same file
that I used as input to create the hash to troll for keys to search
the hash and get the same problem. Please, can someone help me figure
out what I have done wrong.
Here are the simplified files:
fix.txt
a 1
b 2
c 3
d 4
e 5
in.txt
a
b
d
e
and this is the output I get;
$ perl fix.pl
Use of uninitialized value in print at fix.pl line 29,<INKEYS> line
1.
a
Use of uninitialized value in print at fix.pl line 29,<INKEYS> line
2.
b
Use of uninitialized value in print at fix.pl line 29,<INKEYS> line
3.
d
Value EXISTS, but may be undefined.
Value is DEFINED, but may be false.
Value is TRUE at hash key e.
e 5
Use of uninitialized value in concatenation (.) or string at fix.pl
line 33,<INKEYS> line 4.
Hi Addie
I think this is unlikely to be the actual code you are having problems
with. The main problem seems to be that you are assigning to the
variable $key but then printing undeclared variable $var and using it to
index the hash. With 'use strict' in place, any attempt to refer to an
undeclared variable will cause a fatal compilation error, and you will
never see the run time errors you claim you are getting.
It is also worth noting that, if you are unable to control the wrapping
of your posts, it would help us a lot if you indicated which source
lines corresponded to the line numbers flagged in the error messages.
- Rob
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