Std::Random

Seeded pseudo-random number generation.

Module: Std::Random

Each function maps a seed to a value in a requested range using an xorshift mixer. There is no hidden global state.

WARNING

These functions are deterministic: the same seed always produces the same result. They are a stateless hash of the seed, not a running sequence. To get varying values, change the seed each call — for example by seeding from Std::Time::TickMs and advancing it yourself.

import Std::Random;
import Std::Time;
import Std::Io::PrintLine;

func Main() -> int {
    var seed = Time::TickMs();
    for i in 0..3 {
        seed = seed + 1u64;
        PrintLine(Random::RandomInt(1, 7, seed));   // a die roll
    }
    return 0;
}

Functions

Function	Description
RandomInt	Signed integer in [min, max) (int8…int64, int).
RandomUInt	Unsigned integer in [min, max) (uint8…uint64, uint).
RandomFloat	Floating-point value in [min, max] (float32/float64).
RandomBool	A random true/false.

All ranged functions require min < max and abort via Fatal otherwise.