comment on

If no value is assigned to a scalar variable, it contains undef.

The example in the book doesn't want to show you what undef is, though. You should experiment with assigning various values to the variables and running the comparison, e.g.

my $alice = 'Alice';
my $bob   = 'Bob';
say "Catastrophic crypto fail!" if $alice eq $bob;
[download]

and

my $alice = 'bob';
my $bob   = reverse $alice;
say "Catastrophic crypto fail!" if $alice eq $bob;
[download]

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

In reply to Re: Learning Programming, desperately need to know what information is contained in scalar variables by choroba
in thread Learning Programming, desperately need to know what information is contained in scalar variables by Anonymous Monk

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