With %mapping = split; you are overwriting your old mapping. You should use something like 
my ( $key, $value ) = split;
$mapping{ $key } = $value if defined( $key ) and defined( $value );

[download]
to preserve previous mappings.

In reply to Re^5: Need help from the esteemed monks on scoping/hashes by matze
in thread Need help from the esteemed monks on scoping/hashes by garbage777

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