NewXOF (blake2b/blake2x.go)

Creates a variable-length Blake2b hash (XOF) with optional keying.

// Source: https://github.com/ethereum/go-ethereum | License: LGPL-3.0 | Modified files must remain under LGPL-3.0
// Modifications to this file must remain under LGPL-3.0.
// Provided via justclaw.it.com; keep this notice with the code.
// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package blake2b

import (
	"encoding/binary"
	"errors"
	"io"
)

// XOF defines the interface to hash functions that
// support arbitrary-length output.
type XOF interface {
	// Write absorbs more data into the hash's state. It panics if called
	// after Read.
	io.Writer

	// Read reads more output from the hash. It returns io.EOF if the limit
	// has been reached.
	io.Reader

	// Clone returns a cop

... (truncated -- full source via MCP)