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 Declares calling sequences for external procedures written in other
 languages.
 
    DECLARE FUNCTION name [CDECL] [ALIAS "aliasname"] [([parameterlist])]
    DECLARE SUB name [CDECL] [ALIAS "aliasname"] [([parameterlist])]
 
    ■ FUNCTION       External procedure that returns a value; can be used
                     in an expression
 
    ■ SUB            External procedure invoked like a SUB
 
    ■ name           Name used to invoke the procedure; can have up to 40
                     characters, including an explicit type character (%, &,
                     !, #, @, or $)
 
    ■ CDECL          Indicates that the procedure uses C-language argument
                     order, naming conventions, and calling conventions
 
    ■ ALIAS          Indicates that the procedure being called has another
                     name in the .OBJ or library file
 
    ■ aliasname      Name the procedure has in the file or library
 
    ■ parameterlist  One or more arguments in the following form:
 
      [{BYVAL|SEG}] variable [AS type][,[{BYVAL|SEG}] variable [AS type]]...
 
                     • BYVAL      (Default) Indicates the parameter is passed
                                  by value rather than by reference; cannot
                                  be used with a variable of a user-defined
                                  type
 
                     • SEG        Indicates the argument is passed as a
                                  segmented address (far address)
 
                     • variable   Any valid Visual Basic variable name; only
                                  variable type is significant
 
                     • AS type    Data type of the variable: INTEGER, LONG,
                                  SINGLE, DOUBLE, STRING, CURRENCY, ANY,
                                  user-defined type, or two additional types,
                                  FORM and CONTROL
 
 See Also
    ◄CALL[S] Statement (Non-Basic Procedures)►
    ◄DECLARE Statement (Basic Procedures)►