bennofs

let
  # First, let's get a haskellPackages set to play around with
  haskellPackages = (import <nixpkgs> {}).haskellPackages;
  
  # Change the default mtl
  haskellPackagesMtl = haskellPackages.override {
    overrides = self: super: {
      mtl = super.mtl_2_1_3_1;
    };
  };

bennofs

Module overview

Reflex.Class: generic definition of FRP, operations on Events / Behaviors

provides functions for working with events and behaviors

should be imported by users of an FRP-based framework

does not deal with connecting to the outside world, for example creating events from external sources

Reflex.Dynamic: discrete behaviors

Provides the Dynamic data type, a combination of Behavior and Event

Behavior always contains the current value, Event is fired whenever current value changes

-> Behavior is only updated at the end of the current frame, after event propagation

Reflex.Host.Class: generic framework implementation support

bennofs

{ mkDerivation, base, stdenv, time }:
mkDerivation {
  pname = "acme-year";
  version = "2014";
  sha256 = "0zml370s8zv9y60hggv0hlwb3rhmixhdp37cz496dbpffdkw70my";
  libraryHaskellDepends = [ base ];
  testHaskellDepends = [ base time ];
  homepage = "http://github.com/joeyadams/hs-acme-year";
  description = "Get the current year";
  license = stdenv.lib.licenses.publicDomain;

bennofs

Cabal file warning in /data/code/cabal/cabal-install/cabal-install.cabal: Ignoring unknown section type: custom-setup
Cabal file warning in /data/code/cabal/cabal-install/cabal-install.cabal: Ignoring unknown section type: custom-setup
No packages found in snapshot which provide a "ghc" executable, which is a build-tool dependency of "HTTP"
Missing build-tools may be caused by dependencies of the build-tool being overridden by extra-deps.
This should be fixed soon - see this issue https://github.com/commercialhaskell/stack/issues/595

While constructing the BuildPlan the following exceptions were encountered:

--  Failure when adding dependencies:    
      network-uri: needed (==2.6.*), couldn't resolve its dependencies

bennofs

How X11 is started

In the following example, sddm will be used as a display manager. The process is however similar for other display managers in nixpkgs and a summary that applies to all nixpkgs display managers is given at the end.

1. Systemd unit "display-manager.service" starts services.x11.displayManager.job.execCmd (the display manager)

   Code reference: <nixpkgs>/nixos/modules/services/x11/xserver.nix

2. services.x11.displayManager.job.execCmd is set to the path of the sddm binary from the sddm package in the nix store. So SDDM will start and read its configuration from /etc/sddm.conf.

bennofs

with (import <nixpkgs> {}); # get nixpkgs

let
  intero = null; # derivation to build intero goes here

  interoFor = interoEnv: stdenv.mkDerivation {
    buildInputs = [ makeWrapper ];
    buildCommand = ''
      mkdir -p $out/bin 
      for binary in ${intero}/bin/*; do

bennofs

let 
  nixpkgs = (import <nixpkgs> {}).pkgs.fetchFromGitHub {
    owner = "nixos";
    repo = "nixpkgs";
    rev = "964665eb1c75e0bb596e08a92a6c872b5ae06a31";
    sha256 = "11f0hrc9ayba0qqbwrxp7i4nk6vr0vn21943b6c3x8ffdhsl0jzx";
  };
in import nixpkgs {}

bennofs

{
  packageOverrides = pkgs: {
    haskell = pkgs.haskell // {
      packages = pkgs.haskell.packages // {
        ghc7103 = pkgs.haskell.packages.ghc7103 // {
          Glob = pkgs.haskell.lib.overrideCabal pkgs.haskell.packages.ghc7103.Glob (args: {
            buildDepends = (args.buildDepends or []) ++ [pkgs.haskell.packages.ghc7103.semigroups];
          });
        };
      };

bennofs

{
  packageOverrides = pkgs: {
    haskell = pkgs.haskell // {
      packages = pkgs.haskell.packages // {
        ghc7103 = pkgs.haskell.packages.ghc7103.override {
          overrides = self: super: {
            Glob = pkgs.haskell.lib.overrideCabal super.Glob (args: {
              buildDepends = (args.buildDepends or []) ++ [self.semigroups];
            });
          };

bennofs

let
  # Imports
  nixpkgs = import <nixpkgs> {};
  inherit (nixpkgs) lib; 
  inherit (lib) mapAttrs fix extends;

  # Helpers
  makeExtendable = base: 
    fix base // {
      extend = f: makeExtendable (extends f base);