Hi!

I've been unsucessfully trying to modify a hash via its reference: it have only found a lame workaround. Can anyone enlighten me?

Thanks!

Philippe

PS: here's a reduced testcase 

#!/bin/perl -W
#
use strict;
#
my ( %Fruits ) = ( "Apples", 3, "Oranges", 6 );
&Print_Hash;
#
&Modify_Hash_1 ( \%Fruits );
&Print_Hash;
# This doesn't seem to have any effect...
#
&Modify_Hash_2 ( \%Fruits );
&Print_Hash;
# But this does...
#
sub Print_Hash {
  my ( $Fruit );
  foreach $Fruit ( sort ( keys ( %Fruits ) ) ) {
    printf "\n%-7s: %d", $Fruit, $Fruits{$Fruit};
  };
  print "\n\n";
};
#
sub Modify_Hash_1 {
  my ( $Ref_to_Hash ) = @_;
  $Ref_to_Hash = { "Pears", 5, "Peaches", 7 };
};
#
sub Modify_Hash_2 {
  my ( $Ref_to_Hash ) = @_;
  my ( $Fruit );
  foreach $Fruit ( keys ( %$Ref_to_Hash ) ) {
    delete ( $$Ref_to_Hash{$Fruit} );
  };
  $$Ref_to_Hash{"Pears"} = 5;
  $$Ref_to_Hash{"Peaches"} = 7;
};
#
#
__END__

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In reply to Modify a hash via its reference by Philippe

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