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bepascal/docs/NumericalTypes.txt

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+The following table shows correspondences between C/C++ and Pascal numerical types.
+
+References are:
+- FPC Reference guide (v1.0.8).
+- The C Library Reference Guide, by Eric Huss.
+
+
+C/C++ <-> BeAPI <-> Pascal
+==========================
+unsigned char	=	unit8		=	Byte;
+char			=	int8		=	Shortint;
+unsigned int	=	unit16	=	Word;
+short int		=	int16		=	Smallint;
+int			=			=	We use Integer most times for this, but could be Smallint
+unsigned long	=	uint32	=	Longword;
+long			=	int32		=	Longint;
+float			=			=	Single;
+double		=			=	Double;
+long double		=			=	Extended;
+
+
+C/C++ Types
+===========
+Type			Size		Range
+---------------------------------
+unsigned char	8 bits		0 to 255
+char			8 bits		-128 to 127
+unsigned int	16 bits	0 to 65,535
+short int		16 bits	-32,768 to 32,767
+int			16 bits	-32,768 to 32,767
+unsigned long	32 bits	0 to 4,294,967,295
+long			32 bits	-2,147,483,648 to 2,147,483,647
+float			32 bits	1.17549435 * (10^-38) to 3.40282347 * (10^+38)
+double		64 bits	2.2250738585072014 * (10^-308) to 1.7976931348623157 * (10^+308)
+long double		80 bits	3.4 * (10^-4932) to 1.1 * (10^4932)
+
+FPC Pascal Types
+================
+Type		Size		Range
+-----------------------------
+Byte		8 bits		0..255
+ShortInt	8 bits		-128..127
+Word		16 bits	0..65535
+SmallInt	16 bits	-32768..32767
+LongWord	32 bits	0..4294967295
+LongInt	32 bits	-2147483648..2147483647
+
+Integer	16/32/64	either smallint, longint or int64		| These two depends on the
+Cardinal	16/32/64	either word, longword or qword	| compiler mode and platform.
+
+Real		16/32		(depends on the platform)
+Single	32 bits	1.5E-45 .. 3.4E38
+Double	64 bits	5.0E-324 .. 1.7E308
+Extended	80 bits	1.9E-4951 .. 1.1E4932
+
+Int64		64		-9223372036854775808 .. 9223372036854775807
+QWord	64		0 .. 18446744073709551615
+Comp		64		-2E64+1 .. 2E63-1