// Copyright 2018 The Cockroach Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
// implied. See the License for the specific language governing
// permissions and limitations under the License.

package xform

import (
	"fmt"
)

// Operator describes the type of operation that a memo expression performs.
// Some operators are relational (join, select, project) and others are scalar
// (and, or, plus, variable).
type Operator uint16

// String returns the name of the operator as a string.
func (i Operator) String() string {
	if i >= Operator(len(opNames)-1) {
		return fmt.Sprintf("Operator(%d)", i)
	}

	return opNames[opIndexes[i]:opIndexes[i+1]]
}
