As does the semi-colon trick 
my %hash = map {; "$_" => 1 } qw(a b c);

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Update:

I thought I'd better explain this idiom since Lawliet /msg'ed me about it.

Braces in perl are used for hashrefs and for blocks and sometimes perl has to "guess" at the intended meaning. Sometimes (as in this case), perl gets it wrong. The addition of a semicolon convinces perl it's a block, not a hashref.

At least that's how I understand it :-)

Unless I state otherwise, all my code runs with strict and warnings

In reply to Re^2: Puzzling syntax error by FunkyMonk
in thread Puzzling syntax error by saintmike

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