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| author | Ludovic Courtès <ludo@gnu.org> | 2021-01-10 11:53:43 +0100 |
|---|---|---|
| committer | Ludovic Courtès <ludo@gnu.org> | 2021-02-01 17:32:34 +0100 |
| commit | 579506e272cf68649ec68ad8a976a17426ea630c (patch) | |
| tree | b8876de6a6461569445ccac92a8a70adf057dc9c /guix | |
| parent | b41e21488fa1f10bfb4b9c9899139c4e59149894 (diff) | |
utils: Add 'version-unique-prefix'.
* guix/utils.scm (version-unique-prefix): New procedure.
* tests/utils.scm ("version-unique-prefix"): New test.
Diffstat (limited to 'guix')
| -rw-r--r-- | guix/utils.scm | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/guix/utils.scm b/guix/utils.scm index f8b05e7e80..a85e2f495c 100644 --- a/guix/utils.scm +++ b/guix/utils.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org> +;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 Ludovic Courtès <ludo@gnu.org> ;;; Copyright © 2013, 2014, 2015 Mark H Weaver <mhw@netris.org> ;;; Copyright © 2014 Eric Bavier <bavier@member.fsf.org> ;;; Copyright © 2014 Ian Denhardt <ian@zenhack.net> @@ -88,6 +88,7 @@ version-major+minor+point version-major+minor version-major + version-unique-prefix guile-version>? version-prefix? string-replace-substring @@ -589,6 +590,38 @@ minor version numbers from version-string." "Return the major version number as string from the version-string." (version-prefix version-string 1)) +(define (version-unique-prefix version versions) + "Return the shortest version prefix to unambiguously identify VERSION among +VERSIONS. For example: + + (version-unique-prefix \"2.0\" '(\"3.0\" \"2.0\")) + => \"2\" + + (version-unique-prefix \"2.2\" '(\"3.0.5\" \"2.0.9\" \"2.2.7\")) + => \"2.2\" + + (version-unique-prefix \"27.1\" '(\"27.1\")) + => \"\" +" + (define not-dot + (char-set-complement (char-set #\.))) + + (define other-versions + (delete version versions)) + + (let loop ((prefix '()) + (components (string-tokenize version not-dot))) + (define prefix-str + (string-join prefix ".")) + + (if (any (cut string-prefix? prefix-str <>) other-versions) + (match components + ((head . tail) + (loop `(,@prefix ,head) tail)) + (() + version)) + prefix-str))) + (define (version>? a b) "Return #t when A denotes a version strictly newer than B." (eq? '> (version-compare a b))) |