SDK Overview of Level 4

Level 4 Functions

Function level 4	Description
DEFINE_CLASS()	Define a class
DEFINE_PROPERTYGET()	Define a get property
DEFINE_PROPERTYSET()	Define a set property
DEFINE_METHOD()	Define a method
DISPATCH_FACTORY()	Dispatch a factory method
DISPATCH_PROPGET()	Dispatch a get property
DISPATCH_PROPSET()	Dispatch a set property
DISPATCH_METHOD()	Dispatch a method
OBJECT_ASSIGN()	Assign a new object
OBJECT_DELETE()	Delete an existing object
OBJECT_GETARG()	Get argument value
OBJECT_GETARGC()	Get the number of arguments
OBJECT_GETDATA()	Get object's data area
OBJECT_GETOBJECT()	Get an object
OBJECT_GETPARAMETER()	Get parameter value
OBJECT_GETPROPERTY()	Get property value
OBJECT_GETTYPE()	Get parameter type
OBJECT_GETVALUE()	Get value to set property to
OBJECT_NEW()	Create a new object
OBJECT_RETERROR()	Return error
OBJECT_RETPROPERTY()	Return property value
OBJECT_RETRESULT()	Return the value of a result
OBJECT_SETARG()	Set argument value
OBJECT_SETDATA()	Set object's data area
OBJECT_SETPROPERTY()	Set property value

Macros

Level 4 DEFINE_XXX macros are used for defining classes and their associated methods that can be instantiated from the Recital 4GL. The DISPATCH_XXX macros are used to dispatch method calls in an OBJARG format to the specified methods. The OBJECT_XXX macros are use to access and return values passed to and from the object.

OBJARG

The OBJARG format is stored in a string in the format "X:ASCII" where 'X' can be any one of the following:

TYPE	DESCRIPTION
E	Error
C	Character
N	Numeric
L	Logical
D	Date
T	Datetime
Y	Currency
O	Object

OBJPTR

This macro is the pointer to an instantiated object defined by the class.

Object Data Structures

Public properties and methods need to be defined a structure for introspection called public_properties and public_methods. The structures are in an OBJARG format except for the last item which must be defined as an empty string. The string part of the OBJARG is defined as "Name;Type;Description", for example:

static	char	*public_properties[] = {
	"C:CHARVALUE;C;Character property value",
	"C:NUMVALUE;N;Numeric property value",
	"C:LOGVALUE;L;Logical property value",
	"C:DATEVALUE;D;Date property value",
	"C:TIMEVALUE;T;DateTime property value",
	"C:CURRVALUE;Y;Currency property value",
	"C:OBJVALUE;O;Object property value", "",
};
 
static	char	*public_methods[] = {
	"C:DEFINE;L;Define settings in exception",
	"",
};

Return codes

The macros OBJECT_ERROR and OBJECT_SUCCESS are defined to be used to return the result of a method call.