comment on

You need to dereference your values before assigment:

sub my_sub {
   my $scalar_ref = $_[0];
   # note the $$: 
   $$scalar_ref = 'new value';
}
# and call it:
my_sub(\$variable);

# another way, since @_ is an alias:
sub my_sub_2 {
    $_[0] = 3;
}
my $a = 1;
my_sub_2($a);
print $a; # prints 3
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But generally it is better style to modify your values on the caller side, based on the return value of the function.

In reply to Re: Changing local variables in subroutine by passing by reference? by moritz
in thread Changing local variables in subroutine by passing by reference? by why_bird

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