Wouldn't this be considered to be semi-alias? Well you create one more variables but still does not have the "contents" as it is still a pointer/reference. So memory is OK here?

sub alter_var {
    my $aliasvar = $_[0];    # Nice to have C like proto types but...
    ${$aliasvar} =~ s/a/b/g;
#   ${$_[0]} =~ s/a/b/g;   # This uses $_[0] and works
}
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