CHARONE()
 Reduces adjoining duplicate characters in a string to one character
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 Syntax

     CHARONE([<cDeleteCharacters>],<cString>) --> cString

 Arguments

     <cDeleteCharacter>  Designates the characters that have their
     adjoining duplicates removed from <cString>. The default value removes
     all adjoining duplicate characters.

     <cString>  Designates the character string that is processed.

 Returns

     The processed <cString> is returned.

 Description

     CHARONE() searches within the <cString> for repetitions of adjoining
     characters.  When a character is removed, all of the characters but the
     first are deleted.  This differs significantly from the CHARLIST()
     function, where multiple occurrences of characters within the context of
     the string are removed.

 Note

     .  Without the <cDeleteCharacter> parameter, all the repeating
        characters are removed.  If the parameter is specified, only those
        characters in <cDeleteCharacter> are removed.

 Examples

     .  Check for double occurrences of each character in the
        character string:

        ? CHARONE("122333a123")             // "123a123"
        ? CHARONE("A  B  CCCD")             // "A B CD"

     .  Delete multiple side-by-side blanks:

        ? CHARONE(" ", "A  B  A  B")        // "A B A B"

     .  Make the letter "o" only appear once in the character string:

        ? CHARONE("o", "122oooB12o")        // "122oB12"