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A comment on NixOps – Declarative cloud provisioning and deployment with NixOS.

Re:NixOps – Declarative cloud provisioning and deployment wi... by zeisss on Sunday September 17, 2017 @10:20AM (#15269705)
Is there good explanation anywhere of the syntax of those files? I tried getting into nix multiple times and was always put off by the lack of understandability of this.
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Re:NixOps – Declarative cloud provisioning and deployment wi... by zimbatm on Sunday September 17, 2017 @11:05AM (#15269934)
Nix is a bit like JSON + functions.

An object (called attrset in nix):

    { a = 3; b = 4; }
A list:

    [ 1 2 3 4 ];
A string:

     "hello"
A multi-line string:

    ''
      multine
      string
    ''
This defines a lambda with two arguments:

    a: b: a + b;
It's possible to pattern-match arguments. This accepts an attrset with keys a and b, and maps them to local variables:

    { a, b }: a + b;
There are some variations around that like `{ a ? 3 }:` `{ a }@attrs:` and `{ a, ... }`

One special type is the path, which has it's own literal that starts with `./`

To load a file, the `import` keyword is being used. In most cases the whole file is a big lambda function, which gets returned by the import.

Once you know that you can start reading nixpkgs and learn about the building blocks to constructs packages.

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Re:NixOps – Declarative cloud provisioning and deployment wi... by FrozenCow on Sunday September 17, 2017 @12:05PM (#15270238)
Also, for convenience, nested objects/attrsets can be shortened. For instance:

    {
        a = {
            b = {
                c = 3;
            };
        };
    }
can be shortened to:

    {
        a.b.c = 3;
    }
This is used quite often in NixOS system configuration files. There you'll find lines like:

    services.openssh.enable = true;
For a list of all system configuration options that NixOS supports by default see (NixOS options)[https://nixos.org/nixos/options.html].
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Re:NixOps – Declarative cloud provisioning and deployment wi... by abhirag on Sunday September 17, 2017 @11:51AM (#15270151)
I read Nix Pills and they were very informative -- https://nixos.org/nixos/nix-pills/
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Re:NixOps – Declarative cloud provisioning and deployment wi... by olejorgenb on Sunday September 17, 2017 @12:20PM (#15270316)
The nix language: https://nixos.org/nix/manual/#chap-writing-nix-expressions

Abstractions used in nixpkgs: https://nixos.org/nixpkgs/manual/

http://lethalman.blogspot.no/2014/07/nix-pill-1-why-you-shou...

https://medium.com/@MrJamesFisher/nix-by-example-a0063a1a4c5...

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Re:NixOps – Declarative cloud provisioning and deployment wi... by lallysingh on Sunday September 17, 2017 @10:27AM (#15269748)
The syntax is, by far, the most painful part. Change the drop-down to Nix then click on the manual. The website is hard to navigate in that way.
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Re:NixOps – Declarative cloud provisioning and deployment wi... by yaseer on Sunday September 17, 2017 @11:49AM (#15270132)
https://learnxinyminutes.com/docs/nix/

Also includes links to the only other resources I found.

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Re:NixOps – Declarative cloud provisioning and deployment wi... by k__ on Sunday September 17, 2017 @10:37AM (#15269793)
https://medium.com/@MrJamesFisher/nix-by-example-a0063a1a4c5...
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Re:NixOps – Declarative cloud provisioning and deployment wi... by mrkgnao on Sunday September 17, 2017 @11:21AM (#15269999)
https://github.com/knedlsepp/nix-cheatsheet
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