int32
| Property | Value |
|---|---|
| Size | 4 bytes (32 bits) |
| Minimum value | −231 = −2,147,483,648 |
| Maximum value | 231−1 = 2,147,483,647 |
| Literal suffix | i32 |
| Representation | Two's complement |
| Hardware support | Native on all supported targets |
int32 is the workhorse signed integer for general arithmetic — a fixed-width type whose size is identical on every target platform. Like all signed types it uses two's complement: the most significant bit is the sign bit, and the range is asymmetric (the minimum −2,147,483,648 has no positive counterpart).
Literals
let a: int32 = -2000000; // explicit annotation
let b = 42i32; // type suffixIf a literal value does not fit in int32, the compiler emits an error at compile time. See Literals for decimal, hexadecimal, octal, and binary forms.
Typical Use Cases
- General-purpose integer arithmetic
- File offsets on 32-bit systems
- Interop with C
intin FFI signatures
Arithmetic
| Operator | Description | Compound |
|---|---|---|
+ | Addition | += |
- | Subtraction | -= |
* | Multiplication | *= |
/ | Division | /= |
% | Remainder | %= |
** | Exponentiation | n/a |
let a: int32 = 10;
let b: int32 = 3;
let sum = a + b; // 13
let quot = a / b; // 3 truncates toward zero
let rem = a % b; // 1 carries the sign of the dividendDivision and remainder truncate toward zero, so the remainder takes the sign of the dividend: -7 % 2 is -1.
Overflow. In debug builds, signed overflow raises a fatal error. In release builds it wraps modulo 232 in two's-complement fashion. Wraparound is well-defined in Rux (unlike C/C++), but relying on it is almost always a logic error.
Comparison
| Operator | Description | Result |
|---|---|---|
== | Equal | bool |
!= | Not equal | bool |
< | Less than | bool |
<= | Less than or equal | bool |
> | Greater than | bool |
>= | Greater than or equal | bool |
Both operands must have the same type. Comparing int32 with another integer type — or with an unsigned type such as uint32 — is a compile-time error; cast one operand explicitly first.
Shift and Bitwise
Right shift on a signed value is arithmetic: vacated bits are filled with the sign bit, preserving the sign.
let s: int32 = -8;
let r = s >> 2; // -2 sign-filled (arithmetic) right shiftThe bitwise operators &, |, ^, and ~ are also defined (~x equals −(x + 1)), but bitmask work usually reads more clearly on unsigned types.
Conversion
Rux performs no implicit numeric conversions — every conversion uses the as operator. Widening to a wider signed type preserves the value through sign extension; narrowing keeps only the low-order bits; a same-width signed↔unsigned cast reinterprets the bit pattern.
let x: int32 = -1;
let wide = x as int64; // -1 sign-extended, value preserved
let byte = x as int8; // -1 narrowed, low 8 bits kept
let u = x as uint32; // 4294967295 same width, bits reinterpretedSee Also
uint32— unsigned counterpart of the same width- Unsigned Integer Types — the unsigned integer family