Awesome
Nodash - Lodash for Noir
Nodash is a utility library for Noir language.
Installation
Put this into your Nargo.toml.
nodash = { git = "https://github.com/olehmisar/nodash/", tag = "v0.39.3" }
Docs
sqrt
use nodash::sqrt;
assert(sqrt(4 as u64) == 2);
// it floors the result
assert(sqrt(8 as u64) == 2);
clamp
use nodash::clamp;
// if too small, return min
assert(clamp(1 as u64, 2 as u64, 3 as u64) == 2 as u64);
// if too big, return max
assert(clamp(4 as u64, 1 as u64, 3 as u64) == 3 as u64);
// if in range, return value
assert(clamp(2 as u64, 1 as u64, 3 as u64) == 2 as u64);
div_ceil
Calculates a / b
rounded up to the nearest integer.
use nodash::div_ceil;
assert(div_ceil(10 as u64, 3) == 4);
solidity::encode_with_selector
Equivalent to abi.encodeWithSelector
in Solidity.
use nodash::solidity::encode_with_selector;
let selector: u32 = 0xa9059cbb; // transfer(address,uint256)
let args: [Field; 2] = [
0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045, // address
123 // uint256
];
let encoded = encode_with_selector(selector, args);
// typeof encoded: [u8; 68]
field_to_hex
Converts a Field
to a hex string (without 0x
prefix).
let my_hash = 0x0d67824fead966192029093a3aa5c719f2b80262c4f14a5c97c5d70e4b27f2bf;
let expected = "0d67824fead966192029093a3aa5c719f2b80262c4f14a5c97c5d70e4b27f2bf";
assert_eq(field_to_hex(my_hash), expected);
str_to_u64
Converts a string to a u64
.
use nodash::str_to_u64;
assert(str_to_u64("02345678912345678912") == 02345678912345678912);
ord
Returns the ASCII code of a single character.
use nodash::ord;
assert(ord("a") == 97);
ArrayExtensions
slice<L>(start: u32) -> [T; L]
Returns a slice of the array, starting at start
and ending at start + L
. Panics if start + L
is out of bounds.
use nodash::ArrayExtensions;
assert([1, 2, 3, 4, 5].slice::<3>(1) == [2, 3, 4]);
concat
Concatenates two arrays.
use nodash::ArrayExtensions;
assert([1, 2, 3].concat([4, 5]) == [1, 2, 3, 4, 5]);
pad_start
Pads the start of the array with a value.
use nodash::ArrayExtensions;
assert([1, 2, 3].pad_start::<5>(0) == [0, 0, 1, 2, 3]);
pad_end
Pads the end of the array with a value.
use nodash::ArrayExtensions;
assert([1, 2, 3].pad_end::<5>(0) == [1, 2, 3, 0, 0]);
enumerate
Returns an array of tuples, where each tuple contains the index and the value of the array element.
use nodash::ArrayExtensions;
assert(["a", "b", "c"].enumerate() == [(0, "a"), (1, "b"), (2, "c")]);
pack_bytes
Packs [u8; N]
into [Field; N / 31 + 1]
. Useful, if you need to get a hash over bytes. I.e., pedersen_hash(pack_bytes(bytes))
will be MUCH cheaper than pedersen_hash(bytes)
.
use nodash::pack_bytes;
let bytes: [u8; 32] = [0; 32];
let packed = pack_bytes(bytes);