Hello Monks,

I'd like to encode an arbitrary string (may be a perl source in UTF-8 encoding) to a well defined set of characters.

So - something similar to uuencode (pack "u"), but with a defined character set (e.g. only [A-Za-z0-9]) for the encoding string.

Of course, back and forth encoding/decoding should be possible to prevent creation of a write-only device. ;-)

Basically I have only a reduced character set in my "storage" available - about 6bit per character (64 characters) Currently, my best stab at it would be to uuencode the arbitrary string, and do some tr/// on the uuencoded string. Any better ideas?

Update:

I've actually implemented this now for encoding: 
my $uuenc = pack "u", $string;
$uuenc =~ tr/:;"$%&\/()'*#[]<>@`=,.+-/abcdefghijklmnopqrstuvw/;

[download]
and decoding: 
my $uudec = $uuenc;
$uudec =~ tr/abcdefghijklmnopqrstuvw/:;"$%&\/()'*#[]<>@`=,.+-/;
$uudec = unpack "u", $uudec;

[download]
Works for me. My primary objective was to *avoid* specific characters that are used otherwise ( ) < > | , etc.

Bye
 PetaMem     All Perl:   MT, NLP, NLU

In reply to Map octets to set of characters by PetaMem

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