// Copyright 2014 The Cayley Authors. All rights reserved.
//
// 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 graph

// Defines the PrimaryKey interface, this abstracts the generation of IDs

type PrimaryKey interface {
	// Returns a new unique primary key
	Next() PrimaryKey

	// Get the integer format if possible, otherwise logs an error and returns -1
	Int() int64

	// Get the string format
	String() string
}