ethutil/big.go


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package ethutil

import (
    "math/big"
)

var BigInt0 *big.Int = big.NewInt(0)

// True
var BigTrue *big.Int = big.NewInt(1)

// False
var BigFalse *big.Int = big.NewInt(0)

// Big pow
//
// Returns the power of two big integers
func BigPow(a, b int) *big.Int {
    c := new(big.Int)
    c.Exp(big.NewInt(int64(a)), big.NewInt(int64(b)), big.NewInt(0))

    return c
}

// Big
//
// Shortcut for new(big.Int).SetString(..., 0)
func Big(num string) *big.Int {
    n := new(big.Int)
    n.SetString(num, 0)

    return n
}

// BigD
//
// Shortcut for new(big.Int).SetBytes(...)
func BigD(data []byte) *big.Int {
    n := new(big.Int)
    n.SetBytes(data)

    return n
}

// Big to bytes
//
// Returns the bytes of a big integer with the size specified by **base**
// Attempts to pad the byte array with zeros.
func BigToBytes(num *big.Int, base int) []byte {
    ret := make([]byte, base/8)

    return append(ret[:len(ret)-len(num.Bytes())], num.Bytes()...)
}

// Big copy
//
// Creates a copy of the given big integer
func BigCopy(src *big.Int) *big.Int {
    return new(big.Int).Set(src)
}

// Big max
//
// Returns the maximum size big integer
func BigMax(x, y *big.Int) *big.Int {
    if x.Cmp(y) <= 0 {
        return x
    }

    return y
}