Length of Variable Names

  Due to the way assignment to instance (and class) variables is implemented
  in Clipper, there is a limitation on the length of such variable names. By
  treating instance and class variables as though their names are only
  significant to nine characters, no problems will occur.

  Technical Note

  The reason for the nine-character limitation on instance variable names is
  that there are two messages associated with each member variable - the
  name of the variable as specified in the class specification, and the same
  name with an underscore prepended. The Clipper compiler converts
  assignments to member variables into a message send using the modified
  instance variable name. Due to the standard ten character width of the
  Clipper symbol table, a variable with a ten character name effectively has
  the last character truncated for assignment purposes. This means that it
  is not possible to have two variables in a class distinguished only by the
  tenth character of their name.