02-primitive-types.md

+++ title = "2. Primitive Types" weight = 2 +++

2. Primitive Types

Type	C Equivalent	Description
int, uint	int32_t, uint32_t	32-bit signed/unsigned integer
c_char, c_uchar	char, unsigned char	C char / unsigned char (Interop)
c_short, c_ushort	short, unsigned short	C short / unsigned short (Interop)
c_int, c_uint	int, unsigned int	C int / unsigned int (Interop)
c_long, c_ulong	long, unsigned long	C long / unsigned long (Interop)
c_longlong, c_ulonglong	long long, unsigned long long	C long long / unsigned long long (Interop)
I8 .. I128 or i8 .. i128	int8_t .. __int128_t	Signed fixed-width integers
U8 .. U128 or u8 .. u128	uint8_t .. __uint128_t	Unsigned fixed-width integers
isize, usize	ptrdiff_t, size_t	Pointer-sized integers
byte	uint8_t	Alias for U8
F32, F64 or f32, f64	float, double	Floating point numbers
bool	bool	true or false
char	char	Single character
string	char*	C-string (null-terminated)
U0, u0, void	void	Empty type
iN (for example, i256)	_BitInt(N)	Arbitrary bit-width signed integer (C23)
uN (for example, u42)	unsigned _BitInt(N)	Arbitrary bit-width unsigned integer (C23)
rune	uint32_t	Unicode scalar value (UTF-32 code point)

Literals

• Integers: Decimal (123), Hex (0xFF), Octal (0o755), Binary (0b1011).
  • Note: Numbers with leading zeros are treated as decimal (0123 is 123), unlike C.
  • Note: Numbers can contain underscores for readability (1_000_000, 0b_1111_0000).
• Floats: Standard (3.14), Scientific (1e-5, 1.2E3). Floating point numbers also support underscores (3_14.15_92).

Unicode and Runes

Zen C provides first-class support for Unicode scalar values via the rune type. A rune represents a single Unicode code point (encoded as a 32-bit unsigned integer).

Literal	Description
'a'	Standard ASCII character
'🚀'	Multi-byte Unicode character
'\u{2764}'	Unicode escape sequence (Hex)

import "std.zc"

fn main() {
    let c = 'a';
    println "The character '{c}' has a code of {(int)c} in ASCII/Unicode";

    let code = 97;
    println "The code {code} corresponds to the character {(char)code}";

    let r: rune = '🚀';
    println "The rune '{r}' has a code of {(uint)r} in Unicode";
    
    let r_code: uint = 128640;
    println "The code {r_code} corresponds to the rune '{(rune)r_code}'";

    let r_esc: rune = '\u{2764}';
    println "The rune '{r_esc}' has code {(uint)r_esc} (0x{(uint)r_esc:X})";
}

{% alert(type="important") %} Best Practices for Portable Code

• Use Portable Types (int, uint, i64, u8, etc.) for all pure Zen C logic. int is guaranteed to be 32-bit signed on all architectures.
• Use C Interop Types (c_int, c_char, c_long, c_ulong, c_longlong, c_ulonglong) only when interacting with C libraries (FFI). Their size varies by platform and C compiler (e.g. c_long size differs between Windows and Linux).
• Use isize and usize for array indexing and memory pointer arithmetic. {% end %}