bn.rs

bn.js bindings for Rust & WebAssembly with primitive-types support

Write Rust code that uses BN

```rust use std::str::FromStr;

use primitivetypes::{H160, U128}; use wasmbindgen::prelude::*;

use bn_rs::BN;

[wasm_bindgen]

pub fn sum(a: BN, b: BN) -> Result { // BNError implements Into<JsValue>, so we can use ? here let a = u128::tryfrom(a)?; // std uints are supported let b: U128 = b.tryinto()?; // primitive-types uints supported too

let result = a + b.as_u128();

Ok(result.into())

}

[wasm_bindgen]

pub fn isdead(hash: BN) -> Result { let hash = H160::tryfrom(hash)?; // primitive-types hashes supported too let dead = H160::from_str("0x000000000000000000000000000000000000dead").unwrap();

Ok(hash == dead)

} ```

Call it from JavaScript

```javascript import {sum, is_dead} from './pkg' import BN from 'bn.js'

// Initialize bn.js numbers const a = new BN(2, 10) const b = new BN(2, 10)

// Call Rust code with BN passed and returned console.log(sum(a, b)) // == new BN(4, 10) console.log(is_dead(new BN('dead', 'hex'))) // == true ```

Run example

shell $ cd example $ yarn $ yarn start