SCROLLER()

  Short:
  ------
  SCROLLER() Hotkey lookup tables with dbf storage

  Returns:
  --------
  nothing

  Syntax:
  -------
  SET KEY xxx TO SCROLLER

  Description:
  ------------
  Scroller is a hotkey lookup table engine.

  Scroller is data-driven , meaning it operates on data
  stored external to

  the EXE in SCROLLER.DBF.

  SCROLLER() is called via a SET KEY. When called, it
  receives the parameters <cProc> and <cVar> from Clipper, telling
  it the proc and variable the user was sitting on when he pressed
  the hotkey.

  The actual parameters rec'd are <cProc> (proc name),
  <cLine> (line #) and <cVar> (variable name) .<cLine> is ignored,
  but it is included as the 2nd parameter because it is passed by
  Clipper's setkey routines.

  SCROLLER() attempts to find a corresponding record in
  SCROLLER.DBF (which contains fields for proc name and variable).
  SCROLLER.DBF is a storage place for lookup definitions.

  If SCROLLER does not find a matching record, it
  simply closes SCROLLER.DBF and returns to the previous area. It
  then displays a 'lookup table not found' message.

  If SCROLLER finds a matching record, it loads the
  values into memory and closes SCROLLER.DBF. It then opens the
  DBF [and index] of the lookup dbf in the next available area. If
  it is unable to open the dbf, it displays an error message and
  goes back to the previously selected area.

  SCROLLER then draws a box, using the DESCRIPTION
  field as the title, initializes a 1 element array composed of
  the SSTRING (see structure)  expression and calls SMALLS() .

  While in the SMALLS(), first letter searches can be
  done if the dbf is indexed  with a character index. Pressing
  ENTER will KEYBOARD the expression in SRETURN (unless its
  empty), close up the current area and return to the old area.
  Pressing escape just closes things up and returns to the old
  area.

  The KEYBOARD then takes over, feeding the SRETURN
  expression into the keyboard and into the current GET or GETS.

  Examples:
  ---------
   EXTERNAL SCROLLER

   SET KEY -1 TO SCROLLER  && F2

  Notes:
  -------
  BIG NOTE:

  This is really for managing dynamic lookup tables
  that will change frequently as to lookup params. Because of this, it
  is quite complex in nature.

  If you know what the lookup is going to be, and it
  will not change between compiles, look at SMALLS(), SMALLKSET(),
  SMALLVALID() and SMALLWHEN() and use one of these as
  appropriate, instead of SCROLLER().

  Source:
  -------
  S_SCROLL.PRG