CHARUNPACK()
 Decompresses (unpacks) a string
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 Syntax

     CHARUNPACK(<idPackCharacterstring>) --> cString

 Argument

     <idPackCharacterstring>  Designates a string that was previously
     compressed with the CHARPACK() function.

 Returns

     CHARUNPACK() returns an uncompressed string.

 Description

     This function unpacks strings compressed by the CHARPACK() function.
     Notice that the related pack method is automatically recognized.  Since
     we presuppose that the CHARUNPACK() string parameter was compressed
     previously with CHARPACK(), it is assured that the returned string is
     not longer than the maximum permitted under CA-Clipper.

 Example

     The CHARUNPACK() function recreates a string:

     ? CHARUNPACK(CHARPACK("AAAAAAAAAAAA"))   // "AAAAAAAAAAAA"