Philippe:

The problem is that your Modify_Hash_1 routine is accepting the hash ref, and then throwing the reference away by assigning it a new value. By modifying your Modify_Hash_1 routine to the following, you can change the values in %Fruits.

sub Modify_Hash_1 {
  my ( $Ref_to_Hash ) = @_;
  $Ref_to_Hash->{Apples}=5;

# This line would discard the reference to %Fruits, and create a *new*
+ 
# hash with the specified values
#  $Ref_to_Hash = { "Pears", 5, "Peaches", 7 };
};

[download]
...roboticus

Update: s/discards/discard/, s/taking/accepting/, added code tags in explanatory text.

In reply to Re: Modify a hash via its reference by roboticus
in thread Modify a hash via its reference by Philippe

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