Unverified Commit 1ee872a7 authored by Valentin Gagarin's avatar Valentin Gagarin Committed by GitHub
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doc: add a generic section on exploring package sets (#317392) 



this removes the hard-coded listing from the Haskell examples, which can later be replaced by
a dynamic one as for the Python interpreters

* fix broken reference

* clarify why using `nix-env --query` makes sense

Co-authored-by: default avatarwamirez <wamirez@protonmail.com>
parent 0a17504b

doc/languages-frameworks/haskell.section.md

+10 −75
Original line number Diff line number Diff line
@@ -21,25 +21,14 @@ Many “normal” user facing packages written in Haskell, like `niv` or `cachix 
are also exposed at the top level, and there is nothing Haskell specific to

installing and using them.



All of these packages are originally defined in the `haskellPackages` package

set and are re-exposed with a reduced dependency closure for convenience.

(see `justStaticExecutables` or `separateBinOutput` below)

All of these packages are originally defined in the `haskellPackages` package set.

The same packages are re-exposed with a reduced dependency closure for convenience (see `justStaticExecutables` or `separateBinOutput` below).



The `haskellPackages` set includes at least one version of every package from

Hackage as well as some manually injected packages. This amounts to a lot of

packages, so it is hidden from `nix-env -qa` by default for performance reasons.

You can still list all packages in the set like this:

:::{.note}

See [](#chap-language-support) for techniques to explore package sets.

:::



```console

$ nix-env -f '<nixpkgs>' -qaP -A haskellPackages

haskellPackages.a50                                                         a50-0.5

haskellPackages.AAI                                                         AAI-0.2.0.1

haskellPackages.aasam                                                       aasam-0.2.0.0

haskellPackages.abacate                                                     abacate-0.0.0.0

haskellPackages.abc-puzzle                                                  abc-puzzle-0.2.1

…

```

Also, the `haskellPackages` set is included on [search.nixos.org].

The `haskellPackages` set includes at least one version of every package from [Hackage](https://hackage.haskell.org/) as well as some manually injected packages.



The attribute names in `haskellPackages` always correspond with their name on

Hackage. Since Hackage allows names that are not valid Nix without escaping,
@@ -49,8 +38,7 @@ For packages that are part of [Stackage] (a curated set of known to be 
compatible packages), we use the version prescribed by a Stackage snapshot

(usually the current LTS one) as the default version. For all other packages we

use the latest version from [Hackage](https://hackage.org) (the repository of

basically all open source Haskell packages). See [below](#haskell-available-

versions) for a few more details on this.

basically all open source Haskell packages). See [below](#haskell-available-versions) for a few more details on this.



Roughly half of the 16K packages contained in `haskellPackages` don’t actually

build and are [marked as broken semi-automatically](https://github.com/NixOS/nixpkgs/blob/haskell-updates/pkgs/development/haskell-modules/configuration-hackage2nix/broken.yaml).
@@ -63,68 +51,15 @@ How you can help with that is 
described in [Fixing a broken package](#haskell-fixing-a-broken-package).

-->



`haskellPackages` is built with our default compiler, but we also provide other

releases of GHC and package sets built with them. You can list all available

compilers like this:



```console

$ nix-env -f '<nixpkgs>' -qaP -A haskell.compiler

haskell.compiler.ghc810                  ghc-8.10.7

haskell.compiler.ghc90                   ghc-9.0.2

haskell.compiler.ghc925                  ghc-9.2.5

haskell.compiler.ghc926                  ghc-9.2.6

haskell.compiler.ghc927                  ghc-9.2.7

haskell.compiler.ghc92                   ghc-9.2.8

haskell.compiler.ghc945                  ghc-9.4.5

haskell.compiler.ghc946                  ghc-9.4.6

haskell.compiler.ghc947                  ghc-9.4.7

haskell.compiler.ghc94                   ghc-9.4.8

haskell.compiler.ghc963                  ghc-9.6.3

haskell.compiler.ghc96                   ghc-9.6.4

haskell.compiler.ghc98                   ghc-9.8.1

haskell.compiler.ghcHEAD                 ghc-9.9.20231121

haskell.compiler.ghc8107Binary           ghc-binary-8.10.7

haskell.compiler.ghc865Binary            ghc-binary-8.6.5

haskell.compiler.ghc924Binary            ghc-binary-9.2.4

haskell.compiler.integer-simple.ghc8107  ghc-integer-simple-8.10.7

haskell.compiler.integer-simple.ghc810   ghc-integer-simple-8.10.7

haskell.compiler.native-bignum.ghc90     ghc-native-bignum-9.0.2

haskell.compiler.native-bignum.ghc902    ghc-native-bignum-9.0.2

haskell.compiler.native-bignum.ghc925    ghc-native-bignum-9.2.5

haskell.compiler.native-bignum.ghc926    ghc-native-bignum-9.2.6

haskell.compiler.native-bignum.ghc927    ghc-native-bignum-9.2.7

haskell.compiler.native-bignum.ghc92     ghc-native-bignum-9.2.8

haskell.compiler.native-bignum.ghc928    ghc-native-bignum-9.2.8

haskell.compiler.native-bignum.ghc945    ghc-native-bignum-9.4.5

haskell.compiler.native-bignum.ghc946    ghc-native-bignum-9.4.6

haskell.compiler.native-bignum.ghc947    ghc-native-bignum-9.4.7

haskell.compiler.native-bignum.ghc94     ghc-native-bignum-9.4.8

haskell.compiler.native-bignum.ghc948    ghc-native-bignum-9.4.8

haskell.compiler.native-bignum.ghc963    ghc-native-bignum-9.6.3

haskell.compiler.native-bignum.ghc96     ghc-native-bignum-9.6.4

haskell.compiler.native-bignum.ghc964    ghc-native-bignum-9.6.4

haskell.compiler.native-bignum.ghc98     ghc-native-bignum-9.8.1

haskell.compiler.native-bignum.ghc981    ghc-native-bignum-9.8.1

haskell.compiler.native-bignum.ghcHEAD   ghc-native-bignum-9.9.20231121

haskell.compiler.ghcjs                   ghcjs-8.10.7

```

`haskellPackages` is built with our default compiler, but we also provide other releases of GHC and package sets built with them.

Available compilers are collected under `haskell.compiler`.



Each of those compiler versions has a corresponding attribute set built using

Each of those compiler versions has a corresponding attribute set `packages` built with

it. However, the non-standard package sets are not tested regularly and, as a

result, contain fewer working packages. The corresponding package set for GHC

9.4.5 is `haskell.packages.ghc945`. In fact `haskellPackages` is just an alias

for `haskell.packages.ghc964`:



```console

$ nix-env -f '<nixpkgs>' -qaP -A haskell.packages.ghc927

haskell.packages.ghc927.a50                                                         a50-0.5

haskell.packages.ghc927.AAI                                                         AAI-0.2.0.1

haskell.packages.ghc927.aasam                                                       aasam-0.2.0.0

haskell.packages.ghc927.abacate                                                     abacate-0.0.0.0

haskell.packages.ghc927.abc-puzzle                                                  abc-puzzle-0.2.1

…

```



Every package set also re-exposes the GHC used to build its packages as `haskell.packages.*.ghc`.



### Available package versions {#haskell-available-versions}

doc/languages-frameworks/index.md

+48 −0
Original line number Diff line number Diff line
@@ -2,6 +2,54 @@ 


The [standard build environment](#chap-stdenv) makes it easy to build typical Autotools-based packages with very little code. Any other kind of package can be accommodated by overriding the appropriate phases of `stdenv`. However, there are specialised functions in Nixpkgs to easily build packages for other programming languages, such as Perl or Haskell. These are described in this chapter.



Each supported language or software ecosystem has its own package set named `<language or ecosystem>Packages`, which can be explored in various ways:



- Search on [search.nixos.org](https://search.nixos.org/packages)



  For example, search for [`haskellPackages`](https://search.nixos.org/packages?query=haskellPackages) or [`rubyPackages`](https://search.nixos.org/packages?query=rubyPackages).



- Navigate attribute sets with [`nix repl`](https://nixos.org/manual/nix/stable/command-ref/new-cli/nix3-repl).



  This technique is generally useful to inspect Nix language data structures.



  :::{.example #example-navigte-nix-repl}



  # Navigate Java compiler variants in `javaPackages` with `nix repl`



  ```shell-session

  $ nix repl '<nixpkgs>' -I nixpkgs=channel:nixpkgs-unstable

  nix-repl> javaPackages.<tab>

  javaPackages.compiler               javaPackages.openjfx15              javaPackages.openjfx21              javaPackages.recurseForDerivations

  javaPackages.jogl_2_4_0             javaPackages.openjfx17              javaPackages.openjfx22

  javaPackages.mavenfod               javaPackages.openjfx19              javaPackages.override

  javaPackages.openjfx11              javaPackages.openjfx20              javaPackages.overrideDerivation

  ```

  :::



- List all derivations on the command line with [`nix-env --query`](https://nixos.org/manual/nix/stable/command-ref/nix-env/query).



  `nix-env` is the only convenient way to do that, as it will skip attributes that fail [assertions](https://nixos.org/manual/nix/stable/language/constructs#assertions), such as when a package is [marked as broken](#var-meta-broken), rather than failing the entire evaluation.



  :::{.example #example-list-haskellPackages}



  # List all Python packages in Nixpkgs



  The following command lists all [derivations names](https://nixos.org/manual/nix/stable/language/derivations#attr-name) with their attribute path from the latest Nixpkgs rolling release (`nixpkgs-unstable`).



  ```shell-session

  $ nix-env -qaP -f '<nixpkgs>' -A pythonPackages -I nixpkgs=channel:nixpkgs-unstable

  ```



  ```console

  pythonPackages.avahi                                                  avahi-0.8

  pythonPackages.boost                                                  boost-1.81.0

  pythonPackages.caffe                                                  caffe-1.0

  pythonPackages.caffeWithCuda                                          caffe-1.0

  pythonPackages.cbeams                                                 cbeams-1.0.3

  …

  ```

  :::



```{=include=} sections

agda.section.md

android.section.md