nixfmt online demo

let
/*
 * What you're seeing here is our nix formatter. It's quite opinionated:
 */
  sample-01 = { lib }:
{
  list = [
    elem1
    elem2
    elem3
  ] ++ lib.optionals stdenv.isDarwin [
    elem4
    elem5
  ]; # and not quite finished
}; # it will preserve your newlines

sample-02 = { stdenv, lib }:
{
  list =
    [
      elem1
      elem2
      elem3
    ]
    ++ lib.optionals stdenv.isDarwin [ elem4 elem5 ]
    ++ lib.optionals stdenv.isLinux [ elem6 ]
    ;
};
# but it can handle all nix syntax,
# and, in fact, all of nixpkgs in <20s.
# The javascript build is quite a bit slower.
 sample-03 = { stdenv, system }:
assert system == "i686-linux";
stdenv.mkDerivation { };
# these samples are all from https://github.com/nix-community/nix-fmt/tree/master/samples
sample-simple = # Some basic formatting
{
  empty_list = [ ];
  inline_list = [ 1 2 3 ];
  multiline_list = [
    1
    2
    3
    4
  ];
  inline_attrset = { x = "y"; };
  multiline_attrset = {
    a = 3;
    b = 5;
  };
  # some comment over here
  fn = x: x + x;
  relpath = ./hello;
  abspath = /hello;
  # URLs get converted from strings
  url = "https://foobar.com";
  atoms = [ true false null ];
  # Combined
  listOfAttrs = [
    {
      attr1 = 3;
      attr2 = "fff";
    }
    {
      attr1 = 5;
      attr2 = "ggg";
    }
  ];

# long expression
  attrs = {
    attr1 = short_expr;
    attr2 =
      if true then big_expr else big_expr;
  };
}
;
in
[ sample-01 sample-02 sample-03 ]

# nixfmt loading

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