1 // Copyright 2015 The etcd Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 package types 16 17 import "strconv" 18 19 // ID represents a generic identifier which is canonically 20 // stored as a uint64 but is typically represented as a 21 // base-16 string for input/output 22 type ID uint64 23 24 func (i ID) String() string { 25 return strconv.FormatUint(uint64(i), 16) 26 } 27 28 // IDFromString attempts to create an ID from a base-16 string. 29 func IDFromString(s string) (ID, error) { 30 i, err := strconv.ParseUint(s, 16, 64) 31 return ID(i), err 32 } 33 34 // IDSlice implements the sort interface 35 type IDSlice []ID 36 37 func (p IDSlice) Len() int { return len(p) } 38 func (p IDSlice) Less(i, j int) bool { return uint64(p[i]) < uint64(p[j]) } 39 func (p IDSlice) Swap(i, j int) { p[i], p[j] = p[j], p[i] } 40