github.com/holiman/uint256 源码阅读

github.com/holiman/uint256     源码阅读

// uint256: Fixed size 256-bit math library
// Copyright 2018-2020 uint256 Authors
// SPDX-License-Identifier: BSD-3-Clause
 
// Package math provides integer math utilities.
 
package uint256
 
import (
    "encoding/binary"
    "math"
    "math/big"
    "math/bits"
)
 
// Int is represented as an array of 4 uint64, in little-endian order,
// so that Int[3] is the most significant, and Int[0] is the least significant
type Int [4]uint64 //Int定义为一个长度为4的uint64数组. 所以一共4*64位无符号.
// 0是最低位, 3是最高位.
// NewInt returns a new initialized Int.
func NewInt(val uint64) *Int {
    z := &Int{}
    z.SetUint64(val)
    return z
}
 
// SetBytes interprets buf as the bytes of a big-endian unsigned
// integer, sets z to that value, and returns z.
// If buf is larger than 32 bytes