Hallo Habr!
Wir von Typeable wollten eine kurze Reihe von Artikeln darüber veröffentlichen, wie Nix uns bei der Entwicklung hilft (und uns ein wenig behindert). Nachdem wir hier ein wenig nach ähnlichem Material gesucht hatten, waren wir überrascht, dass es keine vernünftige Einführung in Nix auf Habré gibt, auf die man sich beziehen könnte.
@snizovtsev C++, , . :)
?
NixOS, , Nix ( ) Linux. :
$ sh <(curl -L https://nixos.org/nix/install)
Nix
Nix, : Nix nixpkgs , NixOS. .
Nix — . ML (SML, OCaml, Haskell), , , .
.
$ nix repl Welcome to Nix version 2.3.10. Type :? for help. nix-repl>
Nix . , .
nix-repl> "Hello " + "World!" "Hello World!" nix-repl> add = a: b: a + b nix-repl> add 1 2 3
, Nix, .
nix-repl> addOne = add 1 nix-repl> addOne 3 4
, , Nix (attribute sets Nix).
nix-repl> list = [ 1 2 3 ] nix-repl> set = { a = 1; b = list; } nix-repl> set { a = 1; b = [ ... ]; } nix-repl> set.b [ 1 2 3 ]
let...in
. , , , .
fac.nix
:
let fac = n: if n == 0 then 1 else n * fac (n - 1); in { inherit fac; }
inherit
"" . let fac = ... in { fac = fac; }
.
$ nix repl fac.nix Welcome to Nix version 2.3.10. Type :? for help. Loading 'fac.nix'... Added 1 variables. nix-repl> fac 3 6
REPL, Nix , , .
Nix import
, .
mul.nix
:
let mul = a: b: a * b; in { inherit mul; }
fac.nix
:
let multMod = import ./mul.nix; fac = n: if n == 0 then 1 else multMod.mul n (fac (n - 1)); in { inherit fac; }
— , , ? Nix with
, , .
fac.nix
with
:
with import ./mul.nix; let fac = n: if n == 0 then 1 else mul n (fac (n - 1)); in { inherit fac; }
— Nix.
, , , Derivation
. Derivation
— , - . C, "Hello World!", derivation :
Derive([("out","/nix/store/1nq46fyv3629slgxnagqn2c01skp7xrq-hello-world","","")],[("/nix/store/60xqp516mkfhf31n6ycyvxppcknb2dwr-build-hello.drv",["out"])],["/nix/store/wiviq2xyz0ylhl0qcgfgl9221nkvvxfj-hello.c"],"x86_64-linux","/nix/store/r5lh8zg768swlm9hxxfrf9j8gwyadi72-build-hello",[],[("builder","/nix/store/r5lh8zg768swlm9hxxfrf9j8gwyadi72-build-hello"),("name","hello-world"),("out","/nix/store/1nq46fyv3629slgxnagqn2c01skp7xrq-hello-world"),("src","/nix/store/wiviq2xyz0ylhl0qcgfgl9221nkvvxfj-hello.c"),("system","x86_64-linux")])
, , , , , : . , /nix/store
. , Nix , (sandbox). .
, ! , Nix derivation
, .
simple-derivation/default.nix
:
{ pkgs ? import <nixpkgs> {} }: derivation { name = "hello-world"; builder = pkgs.writeShellScript "build-hello" '' ${pkgs.coreutils}/bin/mkdir -p $out/bin ${pkgs.gcc}/bin/gcc $src -o $out/bin/hello -O2 ''; src = ./hello.c; system = builtins.currentSystem; }
. , — , pkgs
. , : import <nixpkgs> {}
.
derivation
— , : name
— , builder
— , src
— , system
— , .
writeShellScript
— nixpkgs
, . Nix .
nix build
, .
$ nix build -f ./simple-derivation/default.nix [1 built] $ ./result/bin/hello Hello World!
nix build
, result
, /nix/store
.
$ ls -l result lrwxrwxrwx 1 user users 50 Mar 29 17:53 result -> /nix/store/vpcddray35g2jrv40dg1809xrmz73awi-simple $ find /nix/store/vpcddray35g2jrv40dg1809xrmz73awi-simple /nix/store/vpcddray35g2jrv40dg1809xrmz73awi-simple /nix/store/vpcddray35g2jrv40dg1809xrmz73awi-simple/bin /nix/store/vpcddray35g2jrv40dg1809xrmz73awi-simple/bin/hello
,
derivation
— , Nix . , cowsay
.
{ lib, stdenv, fetchurl, perl }: stdenv.mkDerivation rec { version = "3.03+dfsg2"; pname = "cowsay"; src = fetchurl { url = "http://http.debian.net/debian/pool/main/c/cowsay/cowsay_${version}.orig.tar.gz"; sha256 = "0ghqnkp8njc3wyqx4mlg0qv0v0pc996x2nbyhqhz66bbgmf9d29v"; }; buildInputs = [ perl ]; postBuild = '' substituteInPlace cowsay --replace "%BANGPERL%" "!${perl}/bin/perl" \ --replace "%PREFIX%" "$out" ''; installPhase = '' mkdir -p $out/{bin,man/man1,share/cows} install -m755 cowsay $out/bin/cowsay ln -s cowsay $out/bin/cowthink install -m644 cowsay.1 $out/man/man1/cowsay.1 ln -s cowsay.1 $out/man/man1/cowthink.1 install -m644 cows/* -t $out/share/cows/ ''; meta = with lib; { description = "A program which generates ASCII pictures of a cow with a message"; homepage = "https://en.wikipedia.org/wiki/Cowsay"; license = licenses.gpl1; platforms = platforms.all; maintainers = [ maintainers.rob ]; }; }
stdenv
— derivation
, : , . — setup
, builder
.
$ nix build nixpkgs.stdenv $ find result/ result/ result/setup result/nix-support $ wc -l result/setup 1330 result/setup
mkDerivation
— , derivation
.
, Arch Linux Gentoo, . , , (buildInputs
) .
Nix . , Nix Typeable, . Stay tuned!
, Nix Nix pills.