From 1dff0fd75b8685558659d6ac44c79fd7e45e1524 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?F=C3=A9lix=20Baylac-Jacqu=C3=A9?= Date: Sat, 6 Feb 2021 19:35:50 +0100 Subject: [PATCH] Create Haskell playground template --- CHANGELOG.md | 5 ++ Main.hs | 4 + Setup.hs | 2 + default.nix | 15 ++++ haskell-playground.cabal | 30 +++++++ nix/sources.json | 26 ++++++ nix/sources.nix | 174 +++++++++++++++++++++++++++++++++++++++ readme.md | 15 ++++ 8 files changed, 271 insertions(+) create mode 100644 CHANGELOG.md create mode 100644 Main.hs create mode 100644 Setup.hs create mode 100644 default.nix create mode 100644 haskell-playground.cabal create mode 100644 nix/sources.json create mode 100644 nix/sources.nix create mode 100644 readme.md diff --git a/CHANGELOG.md b/CHANGELOG.md new file mode 100644 index 0000000..bb7273e --- /dev/null +++ b/CHANGELOG.md @@ -0,0 +1,5 @@ +# Revision history for haskell-playground + +## 0.1.0.0 -- YYYY-mm-dd + +* First version. Released on an unsuspecting world. diff --git a/Main.hs b/Main.hs new file mode 100644 index 0000000..65ae4a0 --- /dev/null +++ b/Main.hs @@ -0,0 +1,4 @@ +module Main where + +main :: IO () +main = putStrLn "Hello, Haskell!" diff --git a/Setup.hs b/Setup.hs new file mode 100644 index 0000000..9a994af --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/default.nix b/default.nix new file mode 100644 index 0000000..444e54d --- /dev/null +++ b/default.nix @@ -0,0 +1,15 @@ +let + sources = import ./nix/sources.nix; + pkgs = import sources.nixpkgs {}; + ghcVersion = "ghc865"; + haskellPackages = pkgs.haskell.packages."${ghcVersion}"; + hlib = pkgs.haskell.lib; +in haskellPackages.developPackage { + name = "haskell-playground"; + root = ./.; + modifier = drv: hlib.overrideCabal drv (attrs: { + buildTools = (attrs.buildTools or []) ++ [ + haskellPackages.cabal-install + ]; + }); +} diff --git a/haskell-playground.cabal b/haskell-playground.cabal new file mode 100644 index 0000000..8c95702 --- /dev/null +++ b/haskell-playground.cabal @@ -0,0 +1,30 @@ +cabal-version: >=1.10 +-- Initial package description 'haskell-playground.cabal' generated by +-- 'cabal init'. For further documentation, see +-- http://haskell.org/cabal/users-guide/ + +name: haskell-playground +version: 0.1.0.0 +-- synopsis: +-- description: +-- bug-reports: +-- license: +license-file: LICENSE +author: Félix Baylac-Jacqué +maintainer: felix@alternativebit.fr +-- copyright: +-- category: +build-type: Simple +extra-source-files: CHANGELOG.md, readme.md + +executable haskell-playground + main-is: Main.hs + -- other-modules: + -- other-extensions: + build-depends: base, + relude, + attoparsec, + megaparsec, + extra + -- hs-source-dirs: + default-language: Haskell2010 diff --git a/nix/sources.json b/nix/sources.json new file mode 100644 index 0000000..1bdc128 --- /dev/null +++ b/nix/sources.json @@ -0,0 +1,26 @@ +{ + "niv": { + "branch": "master", + "description": "Easy dependency management for Nix projects", + "homepage": "https://github.com/nmattia/niv", + "owner": "nmattia", + "repo": "niv", + "rev": "af958e8057f345ee1aca714c1247ef3ba1c15f5e", + "sha256": "1qjavxabbrsh73yck5dcq8jggvh3r2jkbr6b5nlz5d9yrqm9255n", + "type": "tarball", + "url": "https://github.com/nmattia/niv/archive/af958e8057f345ee1aca714c1247ef3ba1c15f5e.tar.gz", + "url_template": "https://github.com///archive/.tar.gz" + }, + "nixpkgs": { + "branch": "release-20.03", + "description": "Nix Packages collection", + "homepage": "", + "owner": "NixOS", + "repo": "nixpkgs", + "rev": "929768261a3ede470eafb58d5b819e1a848aa8bf", + "sha256": "0zi54vbfi6i6i5hdd4v0l144y1c8rg6hq6818jjbbcnm182ygyfa", + "type": "tarball", + "url": "https://github.com/NixOS/nixpkgs/archive/929768261a3ede470eafb58d5b819e1a848aa8bf.tar.gz", + "url_template": "https://github.com///archive/.tar.gz" + } +} diff --git a/nix/sources.nix b/nix/sources.nix new file mode 100644 index 0000000..1938409 --- /dev/null +++ b/nix/sources.nix @@ -0,0 +1,174 @@ +# This file has been generated by Niv. + +let + + # + # The fetchers. fetch_ fetches specs of type . + # + + fetch_file = pkgs: name: spec: + let + name' = sanitizeName name + "-src"; + in + if spec.builtin or true then + builtins_fetchurl { inherit (spec) url sha256; name = name'; } + else + pkgs.fetchurl { inherit (spec) url sha256; name = name'; }; + + fetch_tarball = pkgs: name: spec: + let + name' = sanitizeName name + "-src"; + in + if spec.builtin or true then + builtins_fetchTarball { name = name'; inherit (spec) url sha256; } + else + pkgs.fetchzip { name = name'; inherit (spec) url sha256; }; + + fetch_git = name: spec: + let + ref = + if spec ? ref then spec.ref else + if spec ? branch then "refs/heads/${spec.branch}" else + if spec ? tag then "refs/tags/${spec.tag}" else + abort "In git source '${name}': Please specify `ref`, `tag` or `branch`!"; + in + builtins.fetchGit { url = spec.repo; inherit (spec) rev; inherit ref; }; + + fetch_local = spec: spec.path; + + fetch_builtin-tarball = name: throw + ''[${name}] The niv type "builtin-tarball" is deprecated. You should instead use `builtin = true`. + $ niv modify ${name} -a type=tarball -a builtin=true''; + + fetch_builtin-url = name: throw + ''[${name}] The niv type "builtin-url" will soon be deprecated. You should instead use `builtin = true`. + $ niv modify ${name} -a type=file -a builtin=true''; + + # + # Various helpers + # + + # https://github.com/NixOS/nixpkgs/pull/83241/files#diff-c6f540a4f3bfa4b0e8b6bafd4cd54e8bR695 + sanitizeName = name: + ( + concatMapStrings (s: if builtins.isList s then "-" else s) + ( + builtins.split "[^[:alnum:]+._?=-]+" + ((x: builtins.elemAt (builtins.match "\\.*(.*)" x) 0) name) + ) + ); + + # The set of packages used when specs are fetched using non-builtins. + mkPkgs = sources: system: + let + sourcesNixpkgs = + import (builtins_fetchTarball { inherit (sources.nixpkgs) url sha256; }) { inherit system; }; + hasNixpkgsPath = builtins.any (x: x.prefix == "nixpkgs") builtins.nixPath; + hasThisAsNixpkgsPath = == ./.; + in + if builtins.hasAttr "nixpkgs" sources + then sourcesNixpkgs + else if hasNixpkgsPath && ! hasThisAsNixpkgsPath then + import {} + else + abort + '' + Please specify either (through -I or NIX_PATH=nixpkgs=...) or + add a package called "nixpkgs" to your sources.json. + ''; + + # The actual fetching function. + fetch = pkgs: name: spec: + + if ! builtins.hasAttr "type" spec then + abort "ERROR: niv spec ${name} does not have a 'type' attribute" + else if spec.type == "file" then fetch_file pkgs name spec + else if spec.type == "tarball" then fetch_tarball pkgs name spec + else if spec.type == "git" then fetch_git name spec + else if spec.type == "local" then fetch_local spec + else if spec.type == "builtin-tarball" then fetch_builtin-tarball name + else if spec.type == "builtin-url" then fetch_builtin-url name + else + abort "ERROR: niv spec ${name} has unknown type ${builtins.toJSON spec.type}"; + + # If the environment variable NIV_OVERRIDE_${name} is set, then use + # the path directly as opposed to the fetched source. + replace = name: drv: + let + saneName = stringAsChars (c: if isNull (builtins.match "[a-zA-Z0-9]" c) then "_" else c) name; + ersatz = builtins.getEnv "NIV_OVERRIDE_${saneName}"; + in + if ersatz == "" then drv else + # this turns the string into an actual Nix path (for both absolute and + # relative paths) + if builtins.substring 0 1 ersatz == "/" then /. + ersatz else /. + builtins.getEnv "PWD" + "/${ersatz}"; + + # Ports of functions for older nix versions + + # a Nix version of mapAttrs if the built-in doesn't exist + mapAttrs = builtins.mapAttrs or ( + f: set: with builtins; + listToAttrs (map (attr: { name = attr; value = f attr set.${attr}; }) (attrNames set)) + ); + + # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/lists.nix#L295 + range = first: last: if first > last then [] else builtins.genList (n: first + n) (last - first + 1); + + # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L257 + stringToCharacters = s: map (p: builtins.substring p 1 s) (range 0 (builtins.stringLength s - 1)); + + # https://github.com/NixOS/nixpkgs/blob/0258808f5744ca980b9a1f24fe0b1e6f0fecee9c/lib/strings.nix#L269 + stringAsChars = f: s: concatStrings (map f (stringToCharacters s)); + concatMapStrings = f: list: concatStrings (map f list); + concatStrings = builtins.concatStringsSep ""; + + # https://github.com/NixOS/nixpkgs/blob/8a9f58a375c401b96da862d969f66429def1d118/lib/attrsets.nix#L331 + optionalAttrs = cond: as: if cond then as else {}; + + # fetchTarball version that is compatible between all the versions of Nix + builtins_fetchTarball = { url, name ? null, sha256 }@attrs: + let + inherit (builtins) lessThan nixVersion fetchTarball; + in + if lessThan nixVersion "1.12" then + fetchTarball ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; })) + else + fetchTarball attrs; + + # fetchurl version that is compatible between all the versions of Nix + builtins_fetchurl = { url, name ? null, sha256 }@attrs: + let + inherit (builtins) lessThan nixVersion fetchurl; + in + if lessThan nixVersion "1.12" then + fetchurl ({ inherit url; } // (optionalAttrs (!isNull name) { inherit name; })) + else + fetchurl attrs; + + # Create the final "sources" from the config + mkSources = config: + mapAttrs ( + name: spec: + if builtins.hasAttr "outPath" spec + then abort + "The values in sources.json should not have an 'outPath' attribute" + else + spec // { outPath = replace name (fetch config.pkgs name spec); } + ) config.sources; + + # The "config" used by the fetchers + mkConfig = + { sourcesFile ? if builtins.pathExists ./sources.json then ./sources.json else null + , sources ? if isNull sourcesFile then {} else builtins.fromJSON (builtins.readFile sourcesFile) + , system ? builtins.currentSystem + , pkgs ? mkPkgs sources system + }: rec { + # The sources, i.e. the attribute set of spec name to spec + inherit sources; + + # The "pkgs" (evaluated nixpkgs) to use for e.g. non-builtin fetchers + inherit pkgs; + }; + +in +mkSources (mkConfig {}) // { __functor = _: settings: mkSources (mkConfig settings); } diff --git a/readme.md b/readme.md new file mode 100644 index 0000000..5a3b110 --- /dev/null +++ b/readme.md @@ -0,0 +1,15 @@ +# Haskell Playground + +I use this project to quickly bootstrap a GHCi repl populated with all +the necessary dependencies to have fun with. + +This playground relies on the Haskell Nixpkgs infrastructure to +bootstrap the env, allowing us to download the dependencies from the +NixOS binary cache instead of having to build them by ourselves. + +You can bootstrap the env by via: + +``` +» nix-shell --pure +» ghci +```