Custom function argument list formats

You can enter a function's arguments as a list. If the list has more than one argument, separate the arguments in the list with commas. You can list any number of arguments, but the number of arguments must match the number of arguments that the function accepts.

The following table shows the valid argument types:

Argument type	Meaning	Equivalent C or Windows type
Char	Signed byte	char
Byte	Unsigned byte	unsigned char, BYTE
Short	Signed integer	int, short, BOOL
Word	Unsigned integer	unsigned, HANDLE, HGLOBAL, HWND, UINT, WORD
Long	Signed long integer	Long, LONG
Dword	Unsigned long integer	unsigned long, DWORD
Float	Floating point	float
Double	Double-precision floating point	double
Pointer	Far pointer	far, LPRECT, LPPOINT
String	Far pointer to zero-terminated string	LPCSTR, LPSTR
Void*	No arguments	void, VOID*

* Void signifies that the function accepts no arguments. Void must appear by itself in an argument list.

Internally, Authorware represents all variables and calculated values as signed long integers, double-precision floating point values, or zero-terminated strings. When a custom function is called, the arguments that appear in the expression are converted to the argument type required by the function, according to the rules in the following table:

Required argument type	Integer	Real	String
char, byte, short, word	Truncated	Converted to integer and truncated	Converted to integer and truncated
long, dword	Unchanged	Truncated to signed long integer	Converted to signed long integer
float	Converted to floating- point value	Truncated to floating point value	Converted to floating point value
double	Converted to double-precision floating-point value	Unchanged	Converted to double-precision floating point value
pointer	Unchanged	Truncated to signed long integer	Far pointer to string
string	Far pointer to formatted string representation of value	Far pointer to formatted string representation of value	Far pointer to string

For the pointer argument type, integer values are passed directly. For the string argument type, the value is first converted to a zero-terminated string and then the string's address is passed to the function.

For example, suppose there is a function MyFunc, which requires a single string argument. When it is called with the expression MyFunc(123), Authorware first converts the integer 123 into the zero-terminated string "123" and then passes that string's address to MyFunc.

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