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Almost through the Intermediate Perl book and came across code I do not understand and that was not explained clearly (seems to happen to me frequently in this book!). Here is the code:

sub named { #class method my $self = shift->SUPER::named(@_); my $name = $self->name; my @standings = split ' ', $STANDINGS{$name} || "0 0 0 0"; @$self{qw(wins places shows losses)} = @standings; $self; }

As background: $self is a blessed hash reference. The method 'name' returns a scalar string. %STANDINGS is a hash that is associated with a DBM file.

My question: I do not understand the line  @$self{qw(wins places shows losses)} = @standings;

I see that @standings becomes a list of 4 numbers as a result from splitting on spaces. But, in the next line, "@$self" is syntax for dereferencing an array reference, not a hash reference! Further, the use of the "{" after this indicates a hash, but I have never seen a hash defined in this way. Are they actually saying that you can have a list of keys ("qw(wins places shows losses)") and set the values by setting this to the list "@standings"?? Really?

PERL always seems to confound me with syntax! And when I cannot find the answer in perldocs etc. I just thorw up my hands and post it here!

THANK YOU for being there monks!


In reply to hash deref confusion: Intermediate Perl by live4tech

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