Hello fionbarr,

Suppose you were silly unfortunate enough to have code like this:

 2:56 >perl -wE "my %h = ( A => 'B' ); my $h = { A => 'C' }; say $h{A}
+; say $$h{A}; say $h->{A};"
B
C
C

 3:15 >

[download]

That is, two (separate, unrelated) hashes both called h: a hash named %h, and an unnamed hash accessible via the scalar reference $h. $h{A} and $$h{A} would then be quite different things, but they would look so similar that it would be only too easy to confuse them. In a case like this, the value of the dereference syntax $h->{A} becomes apparent: it makes the dereference operation visually distinctive, and so reduces the danger of confusion.

Anyway, those of use who came to Perl from C++ find the arrow dereference syntax comfortingly familiar; it just “looks right.” ;-)

But, as always, TMTOWTDI, and YMMV.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: dereference hash by Athanasius
in thread dereference hash by fionbarr

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