github.com/m3db/m3@v1.5.0/src/m3ninx/index/segment/empty.go (about)

     1  // Copyright (c) 2018 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package segment
    22  
    23  import "github.com/m3db/m3/src/m3ninx/postings"
    24  
    25  // EmptyOrderedBytesIterator is an empty OrderedBytesIterator.
    26  var EmptyOrderedBytesIterator OrderedBytesIterator = emptyBytesIter{}
    27  
    28  type emptyBytesIter struct{}
    29  
    30  func (e emptyBytesIter) Empty() bool     { return true }
    31  func (e emptyBytesIter) Next() bool      { return false }
    32  func (e emptyBytesIter) Current() []byte { return nil }
    33  func (e emptyBytesIter) Err() error      { return nil }
    34  func (e emptyBytesIter) Close() error    { return nil }
    35  func (e emptyBytesIter) Len() int        { return 0 }
    36  
    37  // EmptyTermsIterator is an empty EmptyTermsIterator.
    38  var EmptyTermsIterator TermsIterator = emptyTermsIter{}
    39  
    40  type emptyTermsIter struct{}
    41  
    42  func (e emptyTermsIter) Empty() bool                      { return true }
    43  func (e emptyTermsIter) Next() bool                       { return false }
    44  func (e emptyTermsIter) Current() ([]byte, postings.List) { return nil, nil }
    45  func (e emptyTermsIter) Err() error                       { return nil }
    46  func (e emptyTermsIter) Close() error                     { return nil }
    47  func (e emptyTermsIter) Len() int                         { return 0 }