Module mice::builder

A builder for rolling stuff. This API affords more flexibility than the basic one. Specifically, it allows a user to provide their own RNG in the place of the default ThreadRng. See rand issue #313 for why this is sometimes necessary.

Here's an example port of the base roll function to JS:

use rand::rngs::StdRng;
use rand::SeedableRng;
use wasm_bindgen::prelude::*;
use js_sys::Math::random;
use mice::{ExpressionResult, builder::RollBuilder};
#[wasm_bindgen]
pub fn roll(input: &str) -> Result<ExpressionResult, JsValue> {
    Ok(RollBuilder::new()
        .parse(input).unwrap()
        .with_rng(Box::new(StdRng::seed_from_u64(random().to_bits())))
        .into_roll().unwrap()
        .roll().unwrap())
}

Note the .with_rng call. Without it, .into_roll() would unavoidably panic on trying to construct a ThreadRng where the underlying rand crate does not support it.

Structs

Roll
RollBuilder

Enums

BuildError