The following (flawed, see below) experiment (prints out the memory location of the static hash) seems to suggest that Perl indeed creates the hash only once:
#!/usr/bin/perl sub static_hash { print { one => 1, two => 2 }; print $/; } static_hash; static_hash; static_hash;
planz$ perl /tmp/static.pl HASH(0x1801380) HASH(0x1801380) HASH(0x1801380)
Update: Okay, forget about that, this just shows that a hash gets created in the same memory location. It could still be a new hash every time. In fact, changing the experiment to use a fresh hash yields exactly the same output:
#!/usr/bin/perl sub static_hash { print { one => $_[0], two => time }; print $/; } static_hash(8); static_hash(9); static_hash(10);

In reply to Re: Does Perl do constant anonymous hash creation optimisation? by Thilosophy
in thread Does Perl do constant anonymous hash creation optimisation? by jaa

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