Sometimes the the implicit aliasing of $_ produces unwanted side effects

e.g in the following code to strip the character "h" from all elements in @arr

my @bla = map { tr/h//d; $_ } @arr;

will also change the entries of @arr.

To avoid this, one needs to write

 my @bla = map { (my $tmp = $_) =~ tr/h//d; $tmp } @arr;

or

my @bla=@arr; 
tr/h//d for @bla;

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Hmm ... I'm wondering if it would make sense to have an alternative non-aliased special var, maybe like $__ such that one could write:

my @bla = map { $__=~tr/h//d; $__ } @arr;

well still not really DRY ...

Any alternative ideas?

Cheers Rolf

UPDATE: alternatively map {tr/h//d; $_} map {$_} @arr

In reply to non aliased default var $_ by LanX

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