github.com/hasnat/dolt/go@v0.0.0-20210628190320-9eb5d843fbb7/store/types/less.go (about)

     1  // Copyright 2019 Dolthub, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  //
    15  // This file incorporates work covered by the following copyright and
    16  // permission notice:
    17  //
    18  // Copyright 2016 Attic Labs, Inc. All rights reserved.
    19  // Licensed under the Apache License, version 2.0:
    20  // http://www.apache.org/licenses/LICENSE-2.0
    21  
    22  package types
    23  
    24  import (
    25  	"github.com/dolthub/dolt/go/store/hash"
    26  )
    27  
    28  type kindAndHash interface {
    29  	Kind() NomsKind
    30  	Hash(*NomsBinFormat) (hash.Hash, error)
    31  }
    32  
    33  func valueLess(nbf *NomsBinFormat, v1, v2 kindAndHash) (bool, error) {
    34  	switch v2.Kind() {
    35  	case UnknownKind:
    36  		return false, ErrUnknownType
    37  
    38  	case BoolKind, FloatKind, StringKind:
    39  		return false, nil
    40  
    41  	default:
    42  		h1, err := v1.Hash(nbf)
    43  
    44  		if err != nil {
    45  			return false, err
    46  		}
    47  
    48  		h2, err := v2.Hash(nbf)
    49  
    50  		if err != nil {
    51  			return false, err
    52  		}
    53  
    54  		return h1.Less(h2), nil
    55  	}
    56  }