> A truly useful use of + is for constructing hashes with map:

> my %hash = map +($_=>undef), @list;

For varying definitions of "useful". This needs 2 letters more than the usual notation

my %hash = map {$_=>undef} @list; °

update

°) see choroba's reply why the parser will have trouble interpreting this.

FWIW: I'd use a hash-slice @hash{@list} = () anyway

Cheers Rolf
(addicted to the Perl Programming Language :)
see Wikisyntax for the Monastery

In reply to Re^8: Passing argument by reference (for a scalar)(Unary Plus) by LanX
in thread Passing argument by reference (for a scalar) by jmClifford

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