empty.go

// Copyright (c) 2018 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

package segment

import "github.com/m3db/m3/src/m3ninx/postings"

// EmptyOrderedBytesIterator is an empty OrderedBytesIterator.
var EmptyOrderedBytesIterator OrderedBytesIterator = emptyBytesIter{}

type emptyBytesIter struct{}

func (e emptyBytesIter) Empty() bool     { return true }
func (e emptyBytesIter) Next() bool      { return false }
func (e emptyBytesIter) Current() []byte { return nil }
func (e emptyBytesIter) Err() error      { return nil }
func (e emptyBytesIter) Close() error    { return nil }
func (e emptyBytesIter) Len() int        { return 0 }

// EmptyTermsIterator is an empty EmptyTermsIterator.
var EmptyTermsIterator TermsIterator = emptyTermsIter{}

type emptyTermsIter struct{}

func (e emptyTermsIter) Empty() bool                      { return true }
func (e emptyTermsIter) Next() bool                       { return false }
func (e emptyTermsIter) Current() ([]byte, postings.List) { return nil, nil }
func (e emptyTermsIter) Err() error                       { return nil }
func (e emptyTermsIter) Close() error                     { return nil }
func (e emptyTermsIter) Len() int                         { return 0 }