chore: Update README

Author: DRBragg

README.md

@@ -3,7 +3,7 @@
 [![Gem Version](https://badge.fury.io/rb/cooklang_rb.svg)](https://badge.fury.io/rb/cooklang_rb)
 [![Ruby](https://github.com/DRBragg/cooklang_rb/actions/workflows/main.yml/badge.svg)](https://github.com/DRBragg/cooklang_rb/actions/workflows/main.yml)
 
-A Ruby parser for [Cooklang](https://cooklang.org/).
+A Ruby parser for [Cooklang](https://cooklang.org/) — compatible with the [v7 spec](https://cooklang.org/docs/spec/).
 
 If you're unfamiliar with [Cooklang](https://cooklang.org/), please visit [https://cooklang.org/](https://cooklang.org/) to learn more about using Cooklang.
 
@@ -26,78 +26,104 @@ Or install it yourself as:
 ## Usage
 
 ```ruby
-source = <<EOF
->> source: https://www.dinneratthezoo.com/wprm_print/6796
->> total time: 6 minutes
->> servings: 2
+source = <<~COOK
+---
+source: https://www.dinneratthezoo.com/wprm_print/6796
+time: 6 minutes
+servings: 2
+---
 
-Place the @apple juice{1,5%cups}, @banana{one sliced}, @frozen mixed berries{1,5%cups} and @vanilla greek yogurt{3/4%cup} in a #blender{}; blend until smooth. If the smoothie seems too thick, add a little more liquid (1/4 cup).
+Place the @apple juice{1.5%cups}, @banana{one sliced}, @frozen mixed berries{1.5%cups} and @vanilla greek yogurt{3/4%cup} in a #blender{}; blend until smooth.
 
 Taste and add @honey{} if desired. Pour into two glasses and garnish with fresh berries and mint sprigs if desired.
-EOF
+COOK
 
 recipe = CooklangRb::Recipe.new(source)
 
 pp recipe.data
 # {
-#  "metadata"=> {...},
-#  "steps"=> [
-#    [...],
-#    [...]
-#  ]
+#   "metadata" => {...},
+#   "steps" => [
+#     [...],
+#     [...]
+#   ]
 # }
 
 pp recipe.metadata
 # {
-#   "source"=>"https://www.dinneratthezoo.com/wprm_print/6796",
-#   "total time"=>"6 minutes",
-#   "servings"=>"2"
+#   "source" => "https://www.dinneratthezoo.com/wprm_print/6796",
+#   "time" => "6 minutes",
+#   "servings" => "2"
 # }
 
 pp recipe.steps
 # [
 #   [
-#     {
-#       "type"=>"text",
-#       "value"=>"Place the "
-#     },
-#     {
-#       "type"=>"ingredient",
-#       "name"=>"apple juice",
-#       "quantity"=>"1,5",
-#       "units"=>"cups"
-#     },
-#     {
-#       "type"=>"text",
-#       "value"=>", "
-#     },
-#     ...
+#     {"type" => "text", "value" => "Place the "},
+#     {"type" => "ingredient", "name" => "apple juice", "quantity" => 1.5, "units" => "cups"},
+#     {"type" => "text", "value" => ", "},
+#     {"type" => "ingredient", "name" => "banana", "quantity" => "one sliced", "units" => ""},
+#     {"type" => "text", "value" => ", "},
+#     {"type" => "ingredient", "name" => "frozen mixed berries", "quantity" => 1.5, "units" => "cups"},
+#     {"type" => "text", "value" => " and "},
+#     {"type" => "ingredient", "name" => "vanilla greek yogurt", "quantity" => 0.75, "units" => "cup"},
+#     {"type" => "text", "value" => " in a "},
+#     {"type" => "cookware", "name" => "blender", "quantity" => 1, "units" => ""},
+#     {"type" => "text", "value" => "; blend until smooth."}
 #   ],
 #   [
-#     {
-#       "type"=>"text",
-#       "value"=>"Taste and add "
-#     },
-#     ...
+#     {"type" => "text", "value" => "Taste and add "},
+#     {"type" => "ingredient", "name" => "honey", "quantity" => "some", "units" => ""},
+#     {"type" => "text", "value" => " if desired. Pour into two glasses and garnish with fresh berries and mint sprigs if desired."}
 #   ]
 # ]
+```
+
+### Metadata
+
+Metadata uses YAML front matter delimited by `---`:
+
+```ruby
+source = <<~COOK
+---
+title: Spaghetti Carbonara
+tags:
+  - pasta
+  - quick
+---
 
+Boil @pasta{500%g} in a #pot{}.
+COOK
+
+recipe = CooklangRb::Recipe.new(source)
+recipe.metadata
+# => {"title" => "Spaghetti Carbonara", "tags" => ["pasta", "quick"]}
+```
+
+### Comments
+
+```ruby
+source = <<~COOK
+-- This is a line comment
+@eggs{2} -- inline comment
+Slowly add @milk{4%cup} [- block comment -], keep mixing
+COOK
 ```
 
-Please visit the [Cooklang Docs](https://cooklang.org/docs) for more information about the Cooklang specification.  Including parser impementations in other languages
+Please visit the [Cooklang Docs](https://cooklang.org/docs) for more information about the Cooklang specification.
 
 ## Development
 
 After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake test` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.
 
 ## Contributing
 
-Bug reports and pull requests are welcome on GitHub at https://github.com/drbragg/cooklang_rb. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [code of conduct](https://github.com/drbragg/cooklang_rb/blob/master/CODE_OF_CONDUCT.md).
+Bug reports and pull requests are welcome on GitHub at https://github.com/drbragg/cooklang_rb. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [code of conduct](https://github.com/drbragg/cooklang_rb/blob/main/CODE_OF_CONDUCT.md).
 
 ## License
 
 The gem is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).
 
 ## Code of Conduct
 
-Everyone interacting in the CooklangRb project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the [code of conduct](https://github.com/drbragg/cooklang_rb/blob/master/CODE_OF_CONDUCT.md).
+Everyone interacting in the CooklangRb project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the [code of conduct](https://github.com/drbragg/cooklang_rb/blob/main/CODE_OF_CONDUCT.md).