1 // Copyright 2023 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package versions 6 7 // This file contains predicates for working with file versions to 8 // decide when a tool should consider a language feature enabled. 9 10 // GoVersions that features in x/tools can be gated to. 11 const ( 12 Go1_18 = "go1.18" 13 Go1_19 = "go1.19" 14 Go1_20 = "go1.20" 15 Go1_21 = "go1.21" 16 Go1_22 = "go1.22" 17 ) 18 19 // Future is an invalid unknown Go version sometime in the future. 20 // Do not use directly with Compare. 21 const Future = "" 22 23 // AtLeast reports whether the file version v comes after a Go release. 24 // 25 // Use this predicate to enable a behavior once a certain Go release 26 // has happened (and stays enabled in the future). 27 func AtLeast(v, release string) bool { 28 if v == Future { 29 return true // an unknown future version is always after y. 30 } 31 return Compare(Lang(v), Lang(release)) >= 0 32 } 33 34 // Before reports whether the file version v is strictly before a Go release. 35 // 36 // Use this predicate to disable a behavior once a certain Go release 37 // has happened (and stays enabled in the future). 38 func Before(v, release string) bool { 39 if v == Future { 40 return false // an unknown future version happens after y. 41 } 42 return Compare(Lang(v), Lang(release)) < 0 43 } 44