Variable types: conversions, etc

	Type	Assignment: type checking, conversions, memory management, etc		When goes out of scope	In expression with operators
	Type	At right can be	Comments	When goes out of scope	In expression with operators
in tr in si c ty pe s	int	any, except structures	from str and lpstr receives string pointer. From BSTR and VARIANT gets numeric value (converts from string if need).		int
	byte	any, except structures	the same		int
	word	any, except structures	the same		int
	long	any, except structures	the same		long
	double	any, except structures	the same		double
	lpstr	strings (lpstr, str, BSTR, VARIANT(BSTR)), byte*, 0	from str and lpstr receives pointer value. BSTR is converted to a hidden local str variable.		lpstr or unsigned int
	str	any, except structures	copies strings, converts numeric types to string	frees string	lpstr or unsigned int
O L E t y p e s	FLOAT	intrinsic and OLE types	converts strings to numeric		double
	DATE	intrinsic and OLE types	the same		double
	CY	intrinsic and OLE types	the same		double
	DECIMAL	intrinsic and OLE types	the same		double
	BSTR	intrinsic and OLE types	copies strings, converts numeric types to string	frees string	double
	VARIANT	any, except structures	copies all data, internally calls AddRef, Release, QueryInterface, etc.	frees/Releases all data	double
	ARRAY	ARRAY of the same type, VARIANT, strings	copies all elements and associated data, calls required functions, etc	the same	cannot be used
	structure	structure of the same type	copies all data, calls required functions, etc	the same	cannot be used
	interface pointer	interface pointer of the same type, 0, IUnknown, IDispatch, VARIANT	Calls AddRef. Calls Release on previous interface pointer. If type differs, calls QueryInterface.	calls Release	cannot be used
po in te rs	pointer	pointer of the same type, 0, byte*	function parameter of reference type also is pointer		pointer or unsigned int
	byte*	pointer of any type, 0, interface pointer, str, lpstr	similar as void* in C, or Any in VB		pointer or unsigned int
	reference	the same as variable	the same as variable	does nothing	the same as variable

Columns:

1. Groups of variable types.

2. Variable type or types.

3. Types that are allowed at right side of assignment operation when at left side is variable of type from column 2. Assignment operation occurs when using operator =, passing argument to function, returning from function (ret).

4. Comments.

5. This column shows how are released associated memory when variable is destroyed (goes out of scope).

6. This column shows how variable is interpreted in expression with operators.

Notes:

1. Type checking is more strict with function arguments, and less strict with = and ret.

2. When a str, BSTR, VARIANT, ARRAY or interface pointer variable is a parameter or return value of a function (except user-defined functions), QM does not copy the associated data and does not call AddRef (the function does it itself, if necessary).

3. A structure is a user-defined type other that listed in this table.