unique.go (2013B)
1 // GoToSocial 2 // Copyright (C) GoToSocial Authors admin@gotosocial.org 3 // SPDX-License-Identifier: AGPL-3.0-or-later 4 // 5 // This program is free software: you can redistribute it and/or modify 6 // it under the terms of the GNU Affero General Public License as published by 7 // the Free Software Foundation, either version 3 of the License, or 8 // (at your option) any later version. 9 // 10 // This program is distributed in the hope that it will be useful, 11 // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 // GNU Affero General Public License for more details. 14 // 15 // You should have received a copy of the GNU Affero General Public License 16 // along with this program. If not, see <http://www.gnu.org/licenses/>. 17 18 package util 19 20 import "net/url" 21 22 // UniqueStrings returns a deduplicated version of the given 23 // slice of strings, without changing the order of the entries. 24 func UniqueStrings(strings []string) []string { 25 var ( 26 l = len(strings) 27 keys = make(map[string]any, l) // Use map to dedupe items. 28 unique = make([]string, 0, l) // Return slice. 29 ) 30 31 for _, str := range strings { 32 // Check if already set as a key in the map; 33 // if not, add to return slice + mark key as set. 34 if _, set := keys[str]; !set { 35 keys[str] = nil // Value doesn't matter. 36 unique = append(unique, str) 37 } 38 } 39 40 return unique 41 } 42 43 // UniqueURIs returns a deduplicated version of the given 44 // slice of URIs, without changing the order of the entries. 45 func UniqueURIs(uris []*url.URL) []*url.URL { 46 var ( 47 l = len(uris) 48 keys = make(map[string]any, l) // Use map to dedupe items. 49 unique = make([]*url.URL, 0, l) // Return slice. 50 ) 51 52 for _, uri := range uris { 53 uriStr := uri.String() 54 55 // Check if already set as a key in the map; 56 // if not, add to return slice + mark key as set. 57 if _, set := keys[uriStr]; !set { 58 keys[uriStr] = nil // Value doesn't matter. 59 unique = append(unique, uri) 60 } 61 } 62 63 return unique 64 }