rand

Pseudo-random number generation.

Types

Rng

Opaque random number generator state.

Functions

new(seed: int, region: Region) -> Rng

Create a new RNG with a deterministic seed.

Parameters

1. seed: int - Seed value.
2. region: Region - Allocation region for RNG state.

Returns

• A new RNG.

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new_time(region: Region) -> Rng

Create a new RNG seeded from the current time.

Parameters

1. region: Region - Allocation region for RNG state.

Returns

• A new RNG.

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next_double(rng: Rng) -> double

Generate a random floating-point number.

Parameters

1. rng: Rng - RNG.

Returns

• Uniform double in [0.0, 1.0).

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next_int(rng: Rng) -> int

Generate a non-negative random integer.

Parameters

1. rng: Rng - RNG.

Returns

• Uniform int in [0, 2^31 - 1].

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throws range_int(rng: Rng, lo: int, hi: int) -> int

Generate a random integer in a half-open interval.

Behavior

• Throws on failure.

Parameters

1. rng: Rng - RNG.
2. lo: int - Lower bound (inclusive).
3. hi: int - Upper bound (exclusive).

Returns

• Uniform int in [lo, hi).