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The problem is that Perl doesn't abstract the concept of appending for its various containers (scalars, arrays, and hashes), because Perl isn't inherently OO. I don't know if Perl 6 is going this route, where you could say:
$foo.append($bar); @foo.append(@bar); %foo.append(%bar);
And in the same vein, perhaps:
$foo.prepend($bar); @foo.prepend(@bar); %foo.prepend(%bar);
In recent Perls, we can write this as:
# append($x, $y) appends $y to $x # etc. # prepend() left as a simple exercise to the reader sub append (\[$@%]\[$@%]) { use Scalar::Util 'reftype'; use Carp qw( croak ); my ($l, $lt, $r, $rt) = map { $_, reftype($_) } @_; if ($lt eq $rt) { if ($lt eq 'SCALAR') { $$l .= $$r; } elsif ($lt eq 'ARRAY') { push @$l, @$r; } elsif ($lt eq 'HASH') { @$l{keys %$r} = values %$r; } else { croak "append($lt,$rt) not implemented"; } } else { croak "append($lt,$rt) not implemented"; } }
I'd expect friction coming from the "what does append/prepend mean for hashes?" faction, but I'd say it's a matter of precedence. Appending to a hash, when there are duplicate keys, uses the new values, and prepending would use the old values.
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: Concerning hash operations (appending, concatenating) by japhy
in thread Concerning hash operations (appending, concatenating) by RazorbladeBidet

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