+++ /dev/null
-package number
-
-import (
- "math/big"
-
- "github.com/vapor/common"
-)
-
-var tt256 = new(big.Int).Lsh(big.NewInt(1), 256)
-var tt256m1 = new(big.Int).Sub(new(big.Int).Lsh(big.NewInt(1), 256), big.NewInt(1))
-var tt255 = new(big.Int).Lsh(big.NewInt(1), 255)
-
-func limitUnsigned256(x *Number) *Number {
- x.num.And(x.num, tt256m1)
- return x
-}
-
-func limitSigned256(x *Number) *Number {
- if x.num.Cmp(tt255) < 0 {
- return x
- } else {
- x.num.Sub(x.num, tt256)
- return x
- }
-}
-
-// Number function
-type Initialiser func(n int64) *Number
-
-// A Number represents a generic integer with a bounding function limiter. Limit is called after each operations
-// to give "fake" bounded integers. New types of Number can be created through NewInitialiser returning a lambda
-// with the new Initialiser.
-type Number struct {
- num *big.Int
- limit func(n *Number) *Number
-}
-
-// Returns a new initialiser for a new *Number without having to expose certain fields
-func NewInitialiser(limiter func(*Number) *Number) Initialiser {
- return func(n int64) *Number {
- return &Number{big.NewInt(n), limiter}
- }
-}
-
-// Return a Number with a UNSIGNED limiter up to 256 bits
-func Uint256(n int64) *Number {
- return &Number{big.NewInt(n), limitUnsigned256}
-}
-
-// Return a Number with a SIGNED limiter up to 256 bits
-func Int256(n int64) *Number {
- return &Number{big.NewInt(n), limitSigned256}
-}
-
-// Returns a Number with a SIGNED unlimited size
-func Big(n int64) *Number {
- return &Number{big.NewInt(n), func(x *Number) *Number { return x }}
-}
-
-// Sets i to sum of x+y
-func (i *Number) Add(x, y *Number) *Number {
- i.num.Add(x.num, y.num)
- return i.limit(i)
-}
-
-// Sets i to difference of x-y
-func (i *Number) Sub(x, y *Number) *Number {
- i.num.Sub(x.num, y.num)
- return i.limit(i)
-}
-
-// Sets i to product of x*y
-func (i *Number) Mul(x, y *Number) *Number {
- i.num.Mul(x.num, y.num)
- return i.limit(i)
-}
-
-// Sets i to the quotient prodject of x/y
-func (i *Number) Div(x, y *Number) *Number {
- i.num.Div(x.num, y.num)
- return i.limit(i)
-}
-
-// Sets i to x % y
-func (i *Number) Mod(x, y *Number) *Number {
- i.num.Mod(x.num, y.num)
- return i.limit(i)
-}
-
-// Sets i to x << s
-func (i *Number) Lsh(x *Number, s uint) *Number {
- i.num.Lsh(x.num, s)
- return i.limit(i)
-}
-
-// Sets i to x^y
-func (i *Number) Pow(x, y *Number) *Number {
- i.num.Exp(x.num, y.num, big.NewInt(0))
- return i.limit(i)
-}
-
-// Setters
-
-// Set x to i
-func (i *Number) Set(x *Number) *Number {
- i.num.Set(x.num)
- return i.limit(i)
-}
-
-// Set x bytes to i
-func (i *Number) SetBytes(x []byte) *Number {
- i.num.SetBytes(x)
- return i.limit(i)
-}
-
-// Cmp compares x and y and returns:
-//
-// -1 if x < y
-// 0 if x == y
-// +1 if x > y
-func (i *Number) Cmp(x *Number) int {
- return i.num.Cmp(x.num)
-}
-
-// Getters
-
-// Returns the string representation of i
-func (i *Number) String() string {
- return i.num.String()
-}
-
-// Returns the byte representation of i
-func (i *Number) Bytes() []byte {
- return i.num.Bytes()
-}
-
-// Uint64 returns the Uint64 representation of x. If x cannot be represented in an int64, the result is undefined.
-func (i *Number) Uint64() uint64 {
- return i.num.Uint64()
-}
-
-// Int64 returns the int64 representation of x. If x cannot be represented in an int64, the result is undefined.
-func (i *Number) Int64() int64 {
- return i.num.Int64()
-}
-
-// Returns the signed version of i
-func (i *Number) Int256() *Number {
- return Int(0).Set(i)
-}
-
-// Returns the unsigned version of i
-func (i *Number) Uint256() *Number {
- return Uint(0).Set(i)
-}
-
-// Returns the index of the first bit that's set to 1
-func (i *Number) FirstBitSet() int {
- for j := 0; j < i.num.BitLen(); j++ {
- if i.num.Bit(j) > 0 {
- return j
- }
- }
-
- return i.num.BitLen()
-}
-
-// Variables
-
-var (
- Zero = Uint(0)
- One = Uint(1)
- Two = Uint(2)
- MaxUint256 = Uint(0).SetBytes(common.Hex2Bytes("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"))
-
- MinOne = Int(-1)
-
- // "typedefs"
- Uint = Uint256
- Int = Int256
-)
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