I don't think I get it. First I thought you mean 

@a = (
  1, 
  2 x!! exists($h{ahoj}),
  3
);

[download]
but that does not autovivify anything in %h (perl 5.8.7). Could you post and example?

Jenda
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In reply to Re^2: Secret Perl Operators: the boolean list squash operator, x!! by Jenda
in thread Secret Perl Operators: the boolean list squash operator, x!! by Aristotle

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