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package intconv
import "math"
// Int64ToInt32 converts v to int32,
// returning an error if it overflows.
func Int64ToInt32(v int64) (int32, error) {
if v < math.MinInt32 || v > math.MaxInt32 {
return 0, ErrOverflow
}
return int32(v), nil
}
// Int64ToUint64 converts v to uint64,
// returning an error if v is negative.
func Int64ToUint64(v int64) (uint64, error) {
if v < 0 {
return 0, ErrOverflow
}
return uint64(v), nil
}
// IntToUint32 converts v to uint32,
// returning an error if it overflows.
func IntToUint32(v int) (uint32, error) {
if v < 0 || v > math.MaxUint32 {
return 0, ErrOverflow
}
return uint32(v), nil
}
// IntToUint64 converts v to uint64,
// returning an error if v is negative.
func IntToUint64(v int) (uint64, error) {
if v < 0 {
return 0, ErrOverflow
}
return uint64(v), nil
}
// SignExtendByteToUint32 sign-extends b
// as a signed 8-bit integer into uint32.
func SignExtendByteToUint32(b byte) uint32 {
if b&0x80 == 0 {
return uint32(b)
}
return 0xFFFFFF00 | uint32(b)
}
// Uint32ToInt converts v to int,
// returning an error if it overflows.
func Uint32ToInt(v uint32) (int, error) {
if uint64(v) > uint64(math.MaxInt) {
return 0, ErrOverflow
}
return int(v), nil
}
// Uint32ToUint8 converts v to uint8,
// returning an error if it overflows.
func Uint32ToUint8(v uint32) (uint8, error) {
if v > math.MaxUint8 {
return 0, ErrOverflow
}
return uint8(v), nil
}
// Uint64ToInt converts v to int,
// returning an error if it overflows.
func Uint64ToInt(v uint64) (int, error) {
if v > uint64(math.MaxInt) {
return 0, ErrOverflow
}
return int(v), nil
}
// Uint64ToInt64 converts v to int64,
// returning an error if it overflows.
func Uint64ToInt64(v uint64) (int64, error) {
if v > math.MaxInt64 {
return 0, ErrOverflow
}
return int64(v), nil
}
// UintptrToInt converts v to int,
// returning an error if it overflows.
func UintptrToInt(v uintptr) (int, error) {
if v > uintptr(math.MaxInt) {
return 0, ErrOverflow
}
return int(v), nil
}
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