1// Copyright (c) 2012-present The upper.io/db authors. All rights reserved. 2// 3// Permission is hereby granted, free of charge, to any person obtaining 4// a copy of this software and associated documentation files (the 5// "Software"), to deal in the Software without restriction, including 6// without limitation the rights to use, copy, modify, merge, publish, 7// distribute, sublicense, and/or sell copies of the Software, and to 8// permit persons to whom the Software is furnished to do so, subject to 9// the following conditions: 10// 11// The above copyright notice and this permission notice shall be 12// included in all copies or substantial portions of the Software. 13// 14// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 15// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 16// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 17// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 18// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 19// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 20// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 21 22package db 23 24// Union represents a compound joined by OR. 25type Union struct { 26 *compound 27} 28 29// Or adds more terms to the compound. 30func (o *Union) Or(orConds ...Compound) *Union { 31 var fn func(*[]Compound) error 32 if len(orConds) > 0 { 33 fn = func(in *[]Compound) error { 34 *in = append(*in, orConds...) 35 return nil 36 } 37 } 38 return &Union{o.compound.frame(fn)} 39} 40 41// Operator returns the OR operator. 42func (o *Union) Operator() CompoundOperator { 43 return OperatorOr 44} 45 46// Empty returns false if this struct holds no conditions. 47func (o *Union) Empty() bool { 48 return o.compound.Empty() 49} 50 51// Or joins conditions under logical disjunction. Conditions can be represented 52// by db.Cond{}, db.Or() or db.And(). 53// 54// Example: 55// 56// // year = 2012 OR year = 1987 57// db.Or( 58// db.Cond{"year": 2012}, 59// db.Cond{"year": 1987}, 60// ) 61func Or(conds ...Compound) *Union { 62 return &Union{newCompound(defaultJoin(conds...)...)} 63} 64