ascii85 - ascii85-encode/decode binary data

       This document, and the package it describes, will undoubtedly contain bugs and  other  problems.   Please
       report such in the category base64 of the TcllibTrackers [http://core.tcl.tk/tcllib/reportlist].  Please
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       Text processing

       Copyright (c) 2010, Emiliano Gavilán

tcllib                                                1.1.1                                        ascii85(3tcl)

       This package provides procedures to encode binary data into ascii85 and back.

       ::ascii85::encode ?-maxlenmaxlen? ?-wrapcharwrapchar? string
              Ascii85  encodes  the  given  binary  string and returns the encoded result. Inserts the character
              wrapchar every maxlen characters of output. wrapchar defaults to newline. maxlen defaults to 76.

              Notewell: If your string is not simple ascii you should fix  the  string  encoding  before  doing
              ascii85 encoding. See the examples.

              The  command  will  throw  an  error for negative values of maxlen, or if maxlen is not an integer
              number.

       ::ascii85::decodestring
              Ascii85 decodes the given string and returns the binary data.  The decoder ignores  whitespace  in
              the string, as well as tabs and newlines.

              % ascii85::encode "Hello, world"
              87cURD_*#TDfTZ)

              % ascii85::encode [string repeat xyz 24]
              G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G
              ^4U[H$X^\H?a^]
              % ascii85::encode -wrapchar "" [string repeat xyz 24]
              G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]G^4U[H$X^\H?a^]

              # NOTE: ascii85 encodes BINARY strings.
              % set chemical [encoding convertto utf-8 "C\u2088H\u2081\u2080N\u2084O\u2082"]
              % set encoded [ascii85::encode $chemical]
              6fN]R8E,5Pidu\UiduhZidua
              % set caffeine [encoding convertfrom utf-8 [ascii85::decode $encoded]]

       ascii85, encoding

       ascii85 - ascii85-encode/decode binary data

       [1]    http://en.wikipedia.org/wiki/Ascii85

       [2]    Postscript       Language       Reference       Manual,      3rd      Edition,      page      131.
              http://www.adobe.com/devnet/postscript/pdfs/PLRM.pdf

       package require Tcl8.59

       package require ascii85?1.1?::ascii85::encode ?-maxlenmaxlen? ?-wrapcharwrapchar? string::ascii85::decodestring

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