I am looking for a explanation of the following transliteration: 
 $str =~ tr|A-Za-z0-9+/| -_|;  # convert to uuencoded format

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I know so far that the "tr///" operator performs a substitution on the individual characters in a string. I know how to build at uuencoded string by hand. By taking the ASCII decimal value of the character, then converting the ASCII to binary. Next shifting the left 6 bits and converting back to decimal. Next, add 32 to the new value to get a ASCII code back (A_Za-z0-9+/). So my question is how does the following do that in one step? 
 $str =~ tr|A-Za-z0-9+/| -_|;

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This code snippet comes from MIME::Base64::Perl decode_base64() function.

In reply to Converting To Uuencoded Format by vegasjoe

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