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 DECLARE {FUNCTION | SUB} name [([parameterlist])]
 
 Usage Notes
   ■ If the variable defined in the parameterlist is an array, it can be
     followed by the number of dimensions in parentheses. For example:
 
         DECLARE SUB DisplayText (A(2) AS STRING)
         DIM Text$(100,5)
         .
         .
         .
         CALL DisplayText(Text$( ))
 
   ■ The number of dimensions is optional; however, the empty parentheses
     should be included.
 
   ■ If a parameter is passed by reference, any change to the parameter
     value inside the procedure changes its value in the calling program.
 
   ■ If a parameter is passed by value, any changes to the parameter value
     inside the procedure is local to that procedure and does not affect its
     value in the calling program.
 
   ■ For calls within Visual Basic, the DECLARE statement is required only if
     you call SUB procedures without the CALL keyword, or if you invoke a
     FUNCTION procedure defined in another module.
 
   ■ A DECLARE statement also causes the compiler to check the number and
     type of arguments used to invoke the procedure. Visual Basic
     automatically generates DECLARE statements when you save your program
     in the programming environment (VBDOS).
 
   ■ The DECLARE statement can appear only in module-level code (not in a
     SUB or FUNCTION procedure) and affects the entire module.
 
   ■ The form of parameterlist determines whether or not argument checking
     is done. For example:
 
         Example                        Description
         ═════════════════════════════  ════════════════════════════════════
         DECLARE SUB First              You can omit the parentheses only if
                                        the SUB or FUNCTION procedure is
                                        separately compiled. No argument
                                        checking is done.
         DECLARE SUB First ()           First has no parameters. Arguments
                                        in a call to First generate an error.
                                        An empty argument list indicates
                                        that the SUB or FUNCTION procedure
                                        has no parameters and that argument
                                        checking should be done.
         DECLARE SUB First (X AS LONG)  First has one long-integer parameter.
                                        The number and type of the arguments
                                        in each call or invocation are
                                        checked when the argument list
                                        appears in the DECLARE statement.
 
   ■ You cannot have fixed-length strings in DECLARE statements. Only
     variable-length strings can be passed to SUB and FUNCTION procedures.
     Fixed-length strings can appear in an argument list but are converted
     to variable-length strings before being passed.
 
   ■ You can have arrays containing fixed-length strings in DECLARE
     statements. The lengths of the array in the CALL statement and the
     declaration must match.