I have confusion about a very simple issue. I am unable to completely understand this simple concepts of 'defined', undef, null strings in perl.

I tried to read a bit and was not sure. I wrote a snippet to explain to you my confusion. 

my $y;

if (defined $y) {
    print "Y is defined\n";
}
else {
    print "Y is not defined\n";
}

if ($y eq "") {
    print "Y is null string\n";
}
else {
    print "Y is not null string\n";
}

[download]

The above gives me 

Y is not defined
Y is null string

[download]
Y is not defined and but it equates to a null string. How does the Perl concepts compare to a language like C. Thank you.

In reply to defined vs null string by Anonymous Monk

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