Random¶

Pseudo-random number generation utilities.

Module: Std::Random

Summary¶

RandomInt8(min: int8, max: int8, seed: uint64) -> int8
RandomInt16(min: int16, max: int16, seed: uint64) -> int16
RandomInt32(min: int32, max: int32, seed: uint64) -> int32
RandomInt64(min: int64, max: int64, seed: uint64) -> int64
RandomInt(min: int, max: int, seed: uint64) -> int

RandomUInt8(min: uint8, max: uint8, seed: uint64) -> uint8
RandomUInt16(min: uint16, max: uint16, seed: uint64) -> uint16
RandomUInt32(min: uint32, max: uint32, seed: uint64) -> uint32
RandomUInt64(min: uint64, max: uint64, seed: uint64) -> uint64
RandomUInt(min: uint, max: uint, seed: uint64) -> uint

RandomFloat32(min: float32, max: float32, seed: uint64) -> float32
RandomFloat64(min: float64, max: float64, seed: uint64) -> float64

RandomBool(seed: uint64) -> bool

Description¶

The Std::Random module provides deterministic pseudo-random number generation functions for integer, floating-point, and boolean values.

All functions require an explicit seed value.

Using the same seed will always produce the same result.

Integer Random Numbers¶

RandomInt8¶

RandomInt8(min: int8, max: int8, seed: uint64) -> int8

Returns a pseudo-random int8 value in the range [min, max).

RandomInt16¶

RandomInt16(min: int16, max: int16, seed: uint64) -> int16

Returns a pseudo-random int16 value in the range [min, max).

RandomInt32¶

RandomInt32(min: int32, max: int32, seed: uint64) -> int32

Returns a pseudo-random int32 value in the range [min, max).

RandomInt64¶

RandomInt64(min: int64, max: int64, seed: uint64) -> int64

Returns a pseudo-random int64 value in the range [min, max).

RandomInt¶

RandomInt(min: int, max: int, seed: uint64) -> int

Returns a pseudo-random platform-sized integer in the range:

[min, max)

Unsigned Integer Random Numbers¶

RandomUInt8¶

RandomUInt8(min: uint8, max: uint8, seed: uint64) -> uint8

Returns a pseudo-random uint8 value in the range [min, max).

RandomUInt16¶

RandomUInt16(min: uint16, max: uint16, seed: uint64) -> uint16

Returns a pseudo-random uint16 value in the range [min, max).

RandomUInt32¶

RandomUInt32(min: uint32, max: uint32, seed: uint64) -> uint32

Returns a pseudo-random uint32 value in the range [min, max).

RandomUInt64¶

RandomUInt64(min: uint64, max: uint64, seed: uint64) -> uint64

Returns a pseudo-random uint64 value in the range [min, max).

RandomUInt¶

RandomUInt(min: uint, max: uint, seed: uint64) -> uint

Returns a pseudo-random platform-sized unsigned integer in the range:

[min, max)

Floating-Point Random Numbers¶

RandomFloat32¶

RandomFloat32(min: float32, max: float32, seed: uint64) -> float32

Returns a pseudo-random float32 value between min and max.

Example¶

let value = RandomFloat32(0.0f32, 1.0f32, seed);

RandomFloat64¶

RandomFloat64(min: float64, max: float64, seed: uint64) -> float64

Returns a pseudo-random float64 value between min and max.

Example¶

let value = RandomFloat64(0.0, 1.0, seed);

Boolean Random Numbers¶

RandomBool¶

RandomBool(seed: uint64) -> bool

Returns either true or false.

Example¶

if RandomBool(seed) {
    Print("Heads");
} else {
    Print("Tails");
}

Examples¶

Random Integer¶

import Std::Random;

let value = RandomInt(1, 101, 12345);

Possible result:

Random Floating-Point Number¶

import Std::Random;

let value = RandomFloat64(
    0.0,
    100.0,
    12345
);

Possible result:

73.28

Random Boolean¶

let result = RandomBool(12345);

Possible result:

true

Errors¶

All range-based functions require:

min < max

If min >= max, the function terminates the program with:

Fatal("min must be less than max")

Notes¶

All functions are deterministic.
The same seed always produces the same result.
Different seeds generally produce different results.
Integer functions generate values in the range [min, max).
Floating-point functions generate values between min and max.
RandomBool() uses the least significant bit of the generated value.
RandomSeed() is planned for a future release

Implementation Notes¶

The module currently uses an internal Xorshift-style pseudo-random number generator.

This generator is:

Fast
Deterministic
Suitable for simulations, testing, and games

It is not cryptographically secure and should not be used for:

Password generation
Cryptographic keys
Security-sensitive randomness
Authentication tokens

For security-sensitive applications, use a cryptographically secure random source instead.