Module evm_coder::custom_signature

A module for custom signature support.

Overview

This module allows you to create arbitrary signatures for types and functions in compile time.

Type signatures

To create the desired type signature, you need to create your own trait with the SIGNATURE constant. Then in the implementation, for the required type, use the macro make_signature

Example

use std::str::from_utf8;
use evm_coder::{custom_signature::SignatureUnit, make_signature};

// Create trait for our signature
trait SoliditySignature {
    const SIGNATURE: SignatureUnit;

    fn name() -> &'static str {
        from_utf8(&Self::SIGNATURE.data[..Self::SIGNATURE.len]).expect("bad utf-8")
    }
}

// Make signatures for some types
impl SoliditySignature for u8 {
    const SIGNATURE: SignatureUnit = make_signature!(new fixed("uint8"));
}
impl SoliditySignature for u32 {
    const SIGNATURE: SignatureUnit = make_signature!(new fixed("uint32"));
}
impl<T: SoliditySignature> SoliditySignature for Vec<T> {
    const SIGNATURE: SignatureUnit = make_signature!(new nameof(T::SIGNATURE) fixed("[]"));
}
impl<A: SoliditySignature, B: SoliditySignature> SoliditySignature for (A, B) {
    const SIGNATURE: SignatureUnit = make_signature!(new fixed("(") nameof(A::SIGNATURE) fixed(",") nameof(B::SIGNATURE) fixed(")"));
}
impl<A: SoliditySignature> SoliditySignature for (A,) {
    const SIGNATURE: SignatureUnit = make_signature!(new fixed("(") nameof(A::SIGNATURE) fixed(",") shift_left(1) fixed(")"));
}

assert_eq!(u8::name(), "uint8");
assert_eq!(<Vec<u8>>::name(), "uint8[]");
assert_eq!(<(u32, u8)>::name(), "(uint32,uint8)");

Example

use core::str::from_utf8;
use evm_coder::{custom_signature::SignatureUnit, make_signature};
// Trait for our signature
trait SoliditySignature {
    const SIGNATURE: SignatureUnit;

    fn name() -> &'static str {
        from_utf8(&Self::SIGNATURE.data[..Self::SIGNATURE.len]).expect("bad utf-8")
    }
}

// Make signatures for some types
impl SoliditySignature for u8 {
    const SIGNATURE: SignatureUnit = make_signature!(new fixed("uint8"));
}
impl<T: SoliditySignature> SoliditySignature for Vec<T> {
    const SIGNATURE: SignatureUnit = make_signature!(new nameof(T::SIGNATURE) fixed("[]"));
}

Structs

SignatureUnit

Storage for the signature or its elements.

Constants

SIGNATURE_SIZE_LIMIT

The maximum length of the signature.