Basic Types

Numeric types

The following table gives an overview of the supported numeric types and their ranges:

kind size	signed integers
	type	min	max
8 bits	i8	-128	127
16 bits	i16	-32768	32768
32 bits	i32	-2147483648	-2147483647
64 bits	i64	-9223372036854775808	9223372036854775807
128 bits	i128 (unsupported so far)	-170141183460469231731687303715884105728	170141183460469231731687303715884105727
dynamic size	int (unsupported so far)	⸺	⸺
kind size	unsigned integers
	type	min	max
8 bits	u8	0	255
16 bits	u16	0	65535
32 bits	u32	0	4294967295
64 bits	u64	0	18446744073709551615
128 bits	u128	0	340282366920938463463374607431768211455
dynamic size	uint (unsupported so far)	0	⸺
kind size	floats
	type	min	max
8 bits	⸺	⸺	⸺
16 bits	f16 (unsupported so far)	9.2E41	3.4E38
32 bits	f32	1.4E−45	3.4E38
64 bits	f64	4.9E−324	1.7976931348623157E308
128 bits	f128 (unsupported so far)	3.4E-4932	1.1897314953572317650857593266280070162E4932
dynamic size	⸺	⸺	⸺

Currently, types i128, f16 and f128 are not supported yet.

The default type of integer constants is currently i32, but this will most likely be changed to i64.

Here is a small example that calculates and prints the ranges of unsigned integer types:

Boolean type

Boolean values true and false are of type bool, which is the required type for conditions used in if statements or in pre- and post-conditions among others.

Note that bool is fully implemented as a choice type of two unit types TRUE and FALSE.

Character types

There is no character type. It seems risky to define a type for the current 17 planes of Unicode code points. UTF-8 can address 32 planes in 4 bytes. Chances are high that someone will find a use for the additional planes or even extend UTF-8 to support more than 4 bytes per code point. Using i32 for a code point seems sufficiently safe for future Unicode changes.

The following gives a small exmple that extracts a slice of codepoints and a slice of bytes from a string to create a new string. Note that some emoji-symbols like ☯️ consist of several codepoints (U+262F U+FE0F, meaning yin-yang symbol U+262F in its graphical form U+FE0F), i.e., these might get modified when single codepoints are copied. Even worse, when single utf8-bytes are copied, non 7-bit ASCII characters may get crippled:

nil type

nil is defined as a unit type feature in the standard library. It is intended to be used to represent the absence of a value. Examples may be a lists tail that is empty or the result of a lookup that failed. See Type unit for more information.

void type

void is defined as an absurd feature in the standard library, i.e. a feature that cannot be instantiated since it requires a void type argument. It is intended to be used to represent the absence of a result. void is the result type of an endless loop or a intrinsic features such as fuzion.std.exit that never would return normally. See Type void for more information.