XPstrLen()
 Get the length of a String for display
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   Function:   XPstrLen()

               Returns the length of a string when supplied to XPdisplay().
               Namely, the ~ characters must be removed..

   Syntax:     XPstrLen(cString) --> nDisplayLen

   Arguments:  a String

   Returns:    It's length when displayed with XPdisplay()

   Usage:      Here's the source code:
               Function XPstrLen(cStr)
               /***
               * Return Length of String for XPdisplay()
               * ie. remove ~
               */
               Return Len(StrTran(cStr,'~'))