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// License: GPLv3 Copyright: 2023, Kovid Goyal, <kovid at kovidgoyal.net>
package random
import (
"crypto/rand"
"fmt"
"math/big"
"golang.org/x/exp/constraints"
)
var _ = fmt.Print
// Return a random integer in the range [0, limit). limit must be > 0
func Int[T constraints.Integer](limit T) T {
b := big.NewInt(int64(limit))
n, err := rand.Int(rand.Reader, b)
if err != nil {
panic(err)
}
return T(n.Uint64())
}
// Return one of items randomnly
func Choice[T any](items ...T) T {
return items[Int(len(items))]
}
// Write randomn bytes into the provided slice
func Bytes(b []byte) {
if _, err := rand.Read(b); err != nil {
panic(err)
}
}
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