Okay, I'm playing around with this just for funz and learninz and I've hit something I'm having trouble explaining: Why does evalnot detect this as an error?

Original command placed in script and executed:

#!/usr/bin/perl
use strict;
use warnings;

print qq{perl version: $] \n};;; 

my $x; 
my %y= ("h"=>1, "i"=>2);  

print $x, $y{x}; 
printf "%s", $x;

exit;

__END__

[download]

Produces, as advertised:

U:\>uninit01.pl
perl version: 5.018002
Use of uninitialized value $x in print at U:\uninit01.pl line 10.
Use of uninitialized value in print at U:\uninit01.pl line 10.
Use of uninitialized value $x in printf at U:\uninit01.pl line 11.

[download]

So I tried to capture the error in an evalblock:

#!/usr/bin/perl
use strict;
use warnings;

print qq{perl version: $] \n};;; 

my $x; 
my %y= ("h"=>1, "i"=>2);  

eval
{
    print $x, $y{x}; 
} ;

# Check for error out of eval{}
if ($@)
{
    # There was an error trapped.
    my $dsperr = $@;
    print "-------------------------\n";
    print "$dsperr\n";
    print "-------------------------\n";
}
else
{
    print "No error found.\n";
}

printf "%s", $x;

exit;

__END__

[download]

But this produced: 

U:\>uninit02.pl
perl version: 5.018002
Use of uninitialized value $x in print at U:\uninit02.pl line 12.
Use of uninitialized value in print at U:\uninit02.pl line 12.
No error found.
Use of uninitialized value $x in printf at U:\uninit02.pl line 29.

[download]

What is it about evalthat I'm not understanding properly here?

In reply to Re: determine the variable causing the error: Use of uninitialized value by marinersk
in thread determine the variable causing the error: Use of uninitialized value by ruqui

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