github.com/dgraph-io/dgraph@v1.2.8/types/compare.go (about) 1 /* 2 * Copyright 2017-2018 Dgraph Labs, Inc. and Contributors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package types 18 19 import "github.com/dgraph-io/dgraph/x" 20 21 // CompareVals compares two values using the given comparison type. 22 // Should be used only in filtering arg1 by comparing with arg2. 23 // arg2 is reference Val to which arg1 is compared. 24 func CompareVals(op string, arg1, arg2 Val) bool { 25 negateRes := func(b bool, e error) (bool, error) { // reverses result 26 return !b, e 27 } 28 noError := func(b bool, e error) bool { 29 return b && e == nil 30 } 31 switch op { 32 case "ge": 33 return noError(negateRes(Less(arg1, arg2))) 34 case "gt": 35 return noError(Less(arg2, arg1)) 36 case "le": 37 return noError(negateRes(Less(arg2, arg1))) 38 case "lt": 39 return noError(Less(arg1, arg2)) 40 case "eq": 41 return noError(Equal(arg1, arg2)) 42 default: 43 // should have been checked at query level. 44 x.Fatalf("Unknown ineqType %v", op) 45 } 46 return false 47 }