package mydb import "git.hexq.cn/tiglog/mydb/internal/adapter" // AndExpr represents an expression joined by a logical conjuction (AND). type AndExpr struct { *adapter.LogicalExprGroup } // And adds more expressions to the group. func (a *AndExpr) And(andConds ...LogicalExpr) *AndExpr { var fn func(*[]LogicalExpr) error if len(andConds) > 0 { fn = func(in *[]LogicalExpr) error { *in = append(*in, andConds...) return nil } } return &AndExpr{a.LogicalExprGroup.Frame(fn)} } // Empty returns false if the expressions has zero conditions. func (a *AndExpr) Empty() bool { return a.LogicalExprGroup.Empty() } // And joins conditions under logical conjunction. Conditions can be // represented by `db.Cond{}`, `db.Or()` or `db.And()`. // // Examples: // // // name = "Peter" AND last_name = "Parker" // db.And( // db.Cond{"name": "Peter"}, // db.Cond{"last_name": "Parker "}, // ) // // // (name = "Peter" OR name = "Mickey") AND last_name = "Mouse" // db.And( // db.Or( // db.Cond{"name": "Peter"}, // db.Cond{"name": "Mickey"}, // ), // db.Cond{"last_name": "Mouse"}, // ) func And(conds ...LogicalExpr) *AndExpr { return &AndExpr{adapter.NewLogicalExprGroup(adapter.LogicalOperatorAnd, conds...)} } var _ = adapter.LogicalExpr(&AndExpr{})