doc: use newer ruby documentation

With the addition of ruby.withPackages, manveru rewrote the nixpkgs
manual section for the ruby language but did not add it to the manual.
This commit replaces the previous documentation with manveru's updated
version.

1 files changed, 11 insertions, 15 deletions

diff --git a/doc/languages-frameworks/ruby.section.md b/doc/languages-frameworks/ruby.section.md
index e4c4ffce0432..61550ddfbbbf 100644
--- a/doc/languages-frameworks/ruby.section.md
+++ b/doc/languages-frameworks/ruby.section.md
@@ -6,11 +6,7 @@ date: 2019-05-23
 
 # Ruby
 
-## User Guide
-
-### Using Ruby
-
-#### Overview
+## Using Ruby
 
 Several versions of Ruby interpreters are available on Nix, as well as over 250 gems and many applications written in Ruby.
 The attribute `ruby` refers to the default Ruby interpreter, which is currently
@@ -37,7 +33,7 @@ Ruby in your environment will be able to find the gem and it can be used in your
 Ruby code (for example via `ruby` or `irb` executables) via `require "nokogiri"`
 as usual.
 
-#### Temporary Ruby environment with `nix-shell`
+### Temporary Ruby environment with `nix-shell`
 
 Rather than having a single Ruby environment shared by all Ruby
 development projects on a system, Nix allows you to create separate
@@ -64,7 +60,7 @@ Again, it's possible to launch the interpreter from the shell. The Ruby
 interpreter has the attribute `gems` which contains all Ruby gems for that
 specific interpreter.
 
-##### Load environment from `.nix` expression
+#### Load Ruby environment from `.nix` expression
 
 As explained in the Nix manual, `nix-shell` can also load an expression from a
 `.nix` file. Say we want to have Ruby 2.5, `nokogori`, and `pry`. Consider a
@@ -87,7 +83,7 @@ What's happening here?
    in the environment. Here, we select the packages `nokogiri` and `pry` from
    the package set.
 
-##### Execute command with `--run`
+#### Execute command with `--run`
 
 A convenient flag for `nix-shell` is `--run`. It executes a command in the
 `nix-shell`. We can e.g. directly open a `pry` REPL:
@@ -108,7 +104,7 @@ Or run a script using this environment:
 nix-shell -p "ruby.withPackages (ps: with ps; [ nokogiri pry ])" --run "ruby example.rb"
 ```
 
-##### Using `nix-shell` as shebang
+#### Using `nix-shell` as shebang
 
 In fact, for the last case, there is a more convenient method. You can add a
 [shebang](https://en.wikipedia.org/wiki/Shebang_(Unix)) to your script
@@ -126,9 +122,9 @@ body = RestClient.get('http://example.com').body
 puts Nokogiri::HTML(body).at('h1').text
 ```
 
-### Developing with Ruby
+## Developing with Ruby
 
-#### Using an existing Gemfile
+### Using an existing Gemfile
 
 In most cases, you'll already have a `Gemfile.lock` listing all your dependencies.
 This can be used to generate a `gemset.nix` which is used to fetch the gems and
@@ -187,7 +183,7 @@ mkShell { buildInputs = [ gems (lowPrio gems.wrappedRuby) ]; }
 ```
 
 
-#### Gem-specific configurations and workarounds
+### Gem-specific configurations and workarounds
 
 In some cases, especially if the gem has native extensions, you might need to
 modify the way the gem is built.
@@ -276,7 +272,7 @@ Of course for this use-case one could also use overlays since the configuration
 for `pg` depends on the `postgresql` alias, but for demonstration purposes this
 has to suffice.
 
-#### Adding a gem to the default gemset
+### Adding a gem to the default gemset
 
 Now that you know how to get a working Ruby environment with Nix, it's time to
 go forward and start actually developing with Ruby.
@@ -297,7 +293,7 @@ To test that it works, you can then try using the gem with:
 NIX_PATH=nixpkgs=$PWD nix-shell -p "ruby.withPackages (ps: with ps; [ name-of-your-gem ])"
 ```
 
-#### Packaging applications
+### Packaging applications
 
 A common task is to add a ruby executable to nixpkgs, popular examples would be
 `chef`, `jekyll`, or `sass`. A good way to do that is to use the `bundlerApp`
@@ -334,7 +330,7 @@ bundlerApp {
 All that's left to do is to generate the corresponding `Gemfile.lock` and
 `gemset.nix` as described above in the `Using an existing Gemfile` section.
 
-##### Packaging executables that require wrapping
+#### Packaging executables that require wrapping
 
 Sometimes your app will depend on other executables at runtime, and tries to
 find it through the `PATH` environment variable.