The "version exceptions" are for Racket versions, for example, the "raco pkg install cover" in a Racket 8.0 installation will query the url: https://pkgs.racket-lang.org/pkg/cover?version=8.0, while the same command in a Racket 6.7 installation will query https://pkgs.racket-lang.org/pkg/cover?version=6.7.
You can check with curl what the responses for each of those queries is. Alex. On Thursday, March 18, 2021 at 1:58:41 AM UTC+8 Jeff Henrikson wrote: > Thanks for the help. > > In fact there are two concepts here, and part of what I think confused you > is something I just discovered this week and plan to report as a bug: > https://pkgs.racket-lang.org/pkgs-all does not include the package's > version . . . > > It seems that the issue you raise applies more generally than to > /pkgs-all. See appended below curl commands that show that the package > version is also missing in the response to a request for information on a > specific package. > > Could it be that the package service is actually deleting old versions of > packages when new ones are uploaded? > > > Jeff > > > curl > https://raw.githubusercontent.com/florence/cover/release/cover-lib/info.rkt > > #lang info > > (define collection 'multi) > (define version "3.3.3") > (define pkg-desc "A code coverage library -- implementation") > > (define deps '("base" > "compiler-lib" > "custom-load" > "data-lib" > "errortrace-lib" > "syntax-color-lib" > "testing-util-lib")) > > curl https://pkgs.racket-lang.org/pkg/cover-lib > > #hasheq((author . "spe...@florence.io") (authors . ("spe...@florence.io")) > (build . #hash((conflicts-log . #f) (dep-failure-log . #f) (docs . ()) > (failure-log . #f) (min-failure-log . #f) (success-log . > "server/built/install/cover-lib.txt") (test-failure-log . #f) > (test-success-log . "server/built/test-success/cover-lib.txt"))) (checksum > . "ad50ffa8f6246053bec24b39b9cae7fad1534373") (checksum-error . #f) > (collection . (multi)) (conflicts . ()) (date-added . 1582684086) > (dependencies . ("base" "compiler-lib" "custom-load" "data-lib" > "errortrace-lib" "syntax-color-lib" "testing-util-lib")) (description . "A > code coverage tool, implementation part") (implies . ()) (last-checked . > 1615994547) (last-edit . 1582684243) (last-updated . 1582839053) (modules . > ((lib "cover/strace.rkt") (lib "cover/cover.rkt") (lib > "cover/private/raw.rkt") (lib "cover/private/format-utils.rkt") (lib > "cover/private/file-utils.rkt") (lib "cover/format.rkt") (lib > "cover/private/contracts.rkt") (lib "cover/main.rkt") (lib > "cover/raco.rkt") (lib "cover/private/shared.rkt") (lib > "cover/private/html/html.rkt"))) (name . "cover-lib") (ring . 1) > (search-terms . #hasheq((:build-success: . #t) (author:spe...@florence.io > . #t) (ring:1 . #t) (testing . #t) (tools . #t))) (source . > "https://github.com/florence/cover.git?path=cover-lib#release"; > <https://github.com/florence/cover.git?path=cover-lib#release>) (tags . > ("testing" "tools")) (versions . #hash((default . #hasheq((checksum . > "ad50ffa8f6246053bec24b39b9cae7fad1534373") (source . > "https://github.com/florence/cover.git?path=cover-lib#release"; > <https://github.com/florence/cover.git?path=cover-lib#release>) > (source_url . > "https://github.com/florence/cover.git?path=cover-lib#release"; > <https://github.com/florence/cover.git?path=cover-lib#release>)))))) > > > On 3/16/21 5:41 PM, Philip McGrath wrote: > > Hi Jeff, > > In fact there are two concepts here, and part of what I think confused you > is something I just discovered this week and plan to report as a bug: > https://pkgs.racket-lang.org/pkgs-all does not include the package's > version: that's what's discussed on the Package Concepts > <https://docs.racket-lang.org/pkg/Package_Concepts.html> page you linked > to. The ?version= query parameter corresponds to the `'versions` (plural—in > hindsight this should have had a different name!) entry in the hash table, > which is documented slightly below the passage you quoted from the section > on Remote and Directory Catalogs > <https://docs.racket-lang.org/pkg/catalog-protocol.html#%28part._.Remote_and_.Directory_.Catalogs%29> > : > >> >> - >> >> 'versions (optional) — a hash table mapping version strings and ' >> default to hash tables, where each version-specific hash table >> provides mappings to override the ones in the main hash table, and ' >> default applies to any version not otherwise mapped. >> >> Clients of a remote catalog may request information for a specific >> version, but they should also check for a 'versions entry in a >> catalog response, in case a catalog with version-specific mappings is >> implemented as a directory or by a file-serving HTTP server. A ' >> default mapping, meanwhile, allows the main hash table to provide >> information that is suitable for clients at version 5.3.6 and earlier >> (which do not check for 'versions). >> >> This field is not a property of the package: it is part of the package > catalog. For example, when registering a package at > https://pkgs.racket-lang.org, you can optionally enter this data in a > field on the web form. The purpose is to implement "version exceptions", > which are documented further down the page—but clearly this section should > be much more pervasively linked to, because this is quite confusing: > >> To make supporting multiple versions of Racket easier, the package >> catalog >> <https://docs.racket-lang.org/pkg/Package_Concepts.html#%28tech._package._catalog%29> >> >> software supports version exceptions. Version exceptions allow package >> authors to specify alternative package source >> <https://docs.racket-lang.org/pkg/Package_Concepts.html#%28tech._package._source%29>s >> >> to be used when installing a given package using a specific version of >> Racket. >> >> For example, a package that uses on Racket 6.0-specific features could >> provide a version exception >> <https://docs.racket-lang.org/pkg/getting-started.html#%28tech._version._exception%29> >> >> for Racket 5.3.6 using a different branch or tag in the package’s GitHub >> repository, or a different zip archive, as package source. Users installing >> the package from Racket 6.0 will use the default source for the package, >> while those using Racket 5.3.5 will install from the alternative branch, >> tag, or archive. >> > This is very rarely useful, in my experience: I thought I might have used > it once, but it now seems I didn't. > > With that confusing detour out of the way, on to your actual question: > "What is the intended use of the version field in the Racket package > manager?" > > The summary you quoted is right, but there are some important details: > > A version is intended to reflect available features of a package, and >> should not be confused with different releases of a package as indicated by >> the checksum. >> > > Let's imagine package A depends on package B. Both are at version 0.0. Now > B exports a new function, which A would like to use. If B is well-behaved, > it has changed its package info.rkt file to include: > >> (define version "0.1") >> > Now A can write: > >> (define deps >> '("base" >> ["B" #:version "0.1"])) >> > and `raco pkg` will prompt anyone who installs or updates A but has an old > version of B to update B, too. > > Note that there are some important differences from the semver systems > used by some other package managers: in particular, by design, the only > possible version constraint is "at least". When you write: > > It seems natural for packages that tightly depend on quickly evolving >> features of the Racket language to have a versioning scheme coupled to >> Racket's own versions. On the other hand, for packages that work with a >> variety of possible Racket versions, it seems to make sense that said >> packages would have their own release cycles, compatibility aspirations, >> and semantic versioning contract. >> > > Racket has some strong views about compatibility, both as a > language/distribution and in the design of its package manager. Racket has, > from my perspective, a fairly remarkable level of commitment to not > breaking existing code. The package system is modeled on an os-level > package manager, a deliberate choice to move away from the intricate > versioning mechanism of the older PLaneT package system. It is focused on > getting your files installed in the right place. The expectation is that > releases of a package will only add functionality, not remove or break it. > A package therefore need only increment the version number if it has added > something that someone else wants to ensure is available. > > If you make a breaking change, the idea is that you should create a new > collection (which may or may not be part of a new package) with a new name: > consider scribble/lp2 > <https://docs.racket-lang.org/scribble/lp.html#(part._scribble_lp2_.Language)> > > and scribble/lp > <https://docs.racket-lang.org/scribble/lp.html#(part._scribble_lp_.Language)> > . > One of the strongest arguments I've seen for this approach is from a > non-Racket context: https://ometer.com/parallel.html (h/t Andy Wingo > <https://www.wingolog.org/archives/2020/02/07/lessons-learned-from-guile-the-ancient-spry> > ) > > If you are familiar with some other package managers, this can sound very > scary, but it has never been a problem at all for me in practice. There is > also an escape hatch, because this is a matter of social norms, not > something automatically enforced: if you call your package, or part of it, > "unstable" or "experimental", like unstable/gui/redex > <https://docs.racket-lang.org/unstable-redex/index.html> or my > adjutor/unstable <https://docs.racket-lang.org/adjutor/Unstable.html>, or > you put a big scary warning in the docs like this > <https://docs.racket-lang.org/ricoeur-tei-utils/Installing___Updating_This_Library.html#%28part._.Status_of_.This_.Library%29> > > (again, one of mine) or this > <https://docs.racket-lang.org/pollen/Unstable_module_reference.html>, you > can follow whatever kind of support practice you want. > > -Philip > > On Tue, Mar 16, 2021 at 6:51 PM Jeff Henrikson <jehen...@gmail.com> wrote: > > Hello racket-users, >> >> As far as I can tell from reading the Racket documentation, the racket >> package manager has only one field to indicate version. I am trying to >> understand the intended use of the version field. >> >> Here the documentation seems to recommend that packages use the version >> field to denote a semantic versioning scheme of for the specific package's >> release cycle: >> >> https://docs.racket-lang.org/pkg/Package_Concepts.html >> a version — a string of the form ‹maj›.‹min›, ‹maj›.‹min›.‹sub›, >> or ‹maj›.‹min›.‹sub›.‹rel›, where ‹maj›, ‹min›, ‹sub›, and ‹rel› are all >> canonical decimal representations of natural numbers, ‹rel› is not 0, ‹sub› >> is not 0 unless ‹rel› is supplied, ‹min› has no more than two digits, and >> ‹sub› and ‹rel› have no more than three digits. A version is intended to >> reflect available features of a package, and should not be confused with >> different releases of a package as indicated by the checksum. >> >> Here the documentation refers to a "Racket version number," which might >> be taken to mean a version number of the Racket language: >> >> https://docs.racket-lang.org/pkg/catalog-protocol.html >> 8.1 Remote and Directory Catalogs >> In the case of a remote URL or a local directory naming a >> package catalog, the URL/path is extended as follows to obtain information >> about packages: >> >> pkg and ‹package› path elements, where ‹package› is a package >> name, plus a version=‹version› query (where ‹version› is a Racket version >> number) in the case of a remote URL. >> >> It seems natural for packages that tightly depend on quickly evolving >> features of the Racket language to have a versioning scheme coupled to >> Racket's own versions. On the other hand, for packages that work with a >> variety of possible Racket versions, it seems to make sense that said >> packages would have their own release cycles, compatibility aspirations, >> and semantic versioning contract. >> >> Note that some package managers for evolving languages have two >> versioning coordinates, one for the language version and one for the >> package version. >> >> Appended below this message is a small racket program that inspects data >> from the https://pkgs.racket-lang.org/pkgs-all HTTP endpoint. According >> to this analysis, 21% of published Racket packages version using version >> numbers of the Racket language. Fewer than 1% of published Racket packages >> seem to version using their own version scheme. And 78% of published >> Racket packages have only ever filled the version field with "default". >> >> As the documentation notes, using checksum instead of a version field is >> sort of like saying any feature can change at any time to any degree: "A >> version is intended to reflect available features of a package, and should >> not be confused with different releases of a package as indicated by the >> checksum." >> >> My question is this: What is the intended use of the version field in the >> Racket package manager? >> >> Thanks in advance, >> >> >> Jeff Henrikson >> >> >> #lang racket >> >> ;; obtain data with: >> ;; curl https://pkgs.racket-lang.org/pkgs-all > contrib_pkgs-all.sexp >> >> >> ;; relfin is "contrib_pkgs-all.sexp" or similar. >> ;; >> ;; In practice it's one value that comes over the wire, so >> ;; we'll just take the car now. >> (define (read-pkgs5 relfin) >> (letrec ( >> (fin (open-input-file relfin)) >> (iter (lambda (xs) >> (let ((x (read fin))) >> (if (not (equal? x eof)) >> (iter (cons x xs)) >> (begin >> (close-input-port fin) >> xs)))))) >> (car (reverse (iter '()))))) >> >> >> ;;; Get the versions of a package hash >> (define (versions-of-pkg pkg) >> (hash-keys (hash-ref pkg 'versions))) >> >> ;;; Is there at least one version that appears to be distinct >> ;;; from a racket version? >> ;; Racket version numbers contemporaneous with the remote catalog >> ;; seem to start around version 6. >> (define (package-uses-version-for-package? pkg) >> (not (empty? (filter (lambda (v) >> (and >> (string? v) >> (string<? v "5"))) >> (versions-of-pkg pkg))))) >> >> >> >> ;;; Is there at least one version that appears to be a racket version? >> ;; Racket version numbers contemporaneous with the remote catalog >> ;; seem to start around version 6. >> (define (package-uses-version-for-racket? pkg) >> (not (empty? (filter (lambda (v) >> (and >> (string? v) >> (not (equal? v "default")) >> (string<? "5" v))) >> (versions-of-pkg pkg))))) >> >> ;;; Histogram the identified uses of the version field >> (define (classify-version-use pkgs) >> (define (how-used pkg) >> (cond >> ((package-uses-version-for-package? pkg) 'package-versioned) >> ((package-uses-version-for-racket? pkg) 'racket-versioned) >> (else 'no-versioning-used))) >> (define (increment x) >> (+ x 1)) >> (let* ( >> (h (make-hash)) >> (_ (for-each (lambda (kv) >> (hash-update! h (how-used (cdr kv)) increment 0)) >> (hash->list pkgs))) >> (num-by-use (hash->list h))) >> num-by-use)) >> >> >> >> (module+ main >> (define pkgs (read-pkgs5 "contrib_pkgs-all.sexp")) >> >> (classify-version-use pkgs) >> ;; '((no-versioning-used . 1472) (racket-versioned . 379) >> (package-versioned . 13)) >> ) >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Racket Users" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to racket-users...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/racket-users/cde363b4-f0c4-eb6f-c68f-7033bfa14c3c%40gmail.com >> >> <https://groups.google.com/d/msgid/racket-users/cde363b4-f0c4-eb6f-c68f-7033bfa14c3c%40gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. 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