printf "grep: %s\n", (join " ... ", grep { $_ }  $$h{a}, $$h{x}, $$h{b}, $$h{c});

Not a problem with grep. $$h{x} is autovivified before grep happens.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re: unexpected modify hash in a distance with grep { $_ } by afoken
in thread unexpected modify hash in a distance with grep { $_ } by leszekdubiel

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