sub inithash {
    my $h= shift;
    $h= { 'a'=>0, ... }; #note the curled braces
    %$h= ( 'a'=>0, ... ); #alternative to the previous line
    }
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The first of these methods, i.e.
    $h= { 'a'=>0, ... };
does not work:

>perl -wMstrict -le
"use Data::Dumper;
 my %hash = qw(a 1  b 2  c 3);
 print Dumper \%hash;
 init(\%hash);
 print Dumper \%hash;
 sub init {
   my $h = shift;
   $h = { foo => 'bar' };
   }
"
$VAR1 = {
          'c' => '3',
          'a' => '1',
          'b' => '2'
        };

$VAR1 = {
          'c' => '3',
          'a' => '1',
          'b' => '2'
        };
[download]