CHARLIST()
 Lists each character in a string
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 Syntax

     CHARLIST(<cString>) --> cString

 Argument

     <cString>  Designates the string that is processed.

 Returns

     CHARLIST() returns a list in which each character in <cString> appears
     only once.

 Description

     CHARLIST() determines the list of characters that appear in the
     <cString>.  Each character only appears in the list once.

 Notes

     .  The CHARLIST() function's return value is never longer than
        256 characters.

     .  If you sort this result with CHARSORT(), you have an ascending
        list of characters.

 Examples

     .  What letters are contained in the text?

        ? CHARLIST("Hello goodbye")                // "Helo gdby"

     .  Show a sorted list of all letters in a text:

        ? CHARSORT(CHARLIST("Hello goodbye"))      // "Hbdegloy"