MoonBit sha1: provide simple sha1 hash algorithm.
// Copyright 2009 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.$ moon version --all
moon 0.1.20261104 (940aa18 2026-11-04) ~/.moon/bin/moon
moonc v0.10.20+65efd5b93 (2026-11-05) ~/.moon/bin/moonc
moonrun 0.1.20261104 (940aa18 2026-11-04) ~/.moon/bin/moonrun
type Digestimpl ByteWriter for Digest