You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: ed25519.go
    path of file: ./repos/sliver/vendor/github.com/hdevalence/ed25519consensus
    
    the code of the file until where you have to start completion: // Copyright 2016 The Go Authors. All rights reserved.
// Copyright 2016 Henry de Valence. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package ed25519consensus implements Ed25519 verification according to ZIP215.
package ed25519consensus

import (
	"crypto/ed25519"
	"crypto/sha512"

	"filippo.io/edwards25519"
)

// Verify reports whether sig is a valid signature of message by
// publicKey, using precisely-specified validation criteria (ZIP 215) suitable
// for use in consensus-critical contexts.
func Verify(publicKey ed25519.PublicKey, message, sig []byte) bool {
	if l := len(publicKey); l != ed25519.PublicKeySize {
		return false
	}

	if len(sig) != ed25519.SignatureSize || sig[63]&224
    
func Verify(publicKey ed25519.PublicKey, message, sig []byte) bool {
	if l := len(publicKey); l != ed25519.PublicKeySize {
		return false
	}

	if len(sig) != ed25519.SignatureSize || sig[63]&224 != 0 {
		return false
	}

	// ZIP215: this works because SetBytes does not check that encodings are canonical.
	A, err := new(edwards25519.Point).SetBytes(publicKey)
	if err != nil {
		return false
	}
	A.Negate(A)

	h := sha512.New()
	h.Write(sig[:32])
	h.Write(publicKey[:])
	h.Write(message)
	var digest [64]byte
	h.Sum(digest[:0])

	hReduced, err := new(edwards25519.Scalar).SetUniformBytes(digest[:])
	if err != nil {
		return false
	}

	// ZIP215: this works because SetBytes does not check that encodings are canonical.
	checkR, err := new(edwards25519.Point).SetBytes(sig[:32])
	if err != nil {
		return false
	}

	// https://tools.ietf.org/html/rfc8032#section-5.1.7 requires that s be in
	// the range [0, order) in order to prevent signature malleability.
	// ZIP215: This is also required by ZIP215.
	s, err := new(edwards25519.Scalar).SetCanonicalBytes(sig[32:])
	if err != nil {
		return false
	}

	R := new(edwards25519.Point).VarTimeDoubleScalarBaseMult(hReduced, A, s)

	// ZIP215: We want to check [8](R - checkR) == 0
	p := new(edwards25519.Point).Subtract(R, checkR) // p = R - checkR
	p.MultByCofactor(p)
	return p.Equal(edwards25519.NewIdentityPoint()) == 1 // p == 0
}