Defines various methods for adding hooks of a specific type.

The declaration defines the name and type of hook. It should be a type declaration in the form: some_hook : ExampleHook, where some_hook is the name of the hook, and ExampleHook is type type.

A default order can be specified by order. The order argument must be append or prepend. This indicates the order hooks are added by default when called by client code.

Multiple methods are generated. The primary methods will be named the same as the hook (from declaration). These take a pre-built hook instance, or arguments to pass to the hook type's initializer. The new hook is added a collection in the order specified by order.

A private getter method is created so that the hooks can be accessed if needed. The getter method has _hooks appended to the hook name. For instance, if the declaration contains important_thing, then the getter is important_thing_hooks.

Lastly, an optional block can be provided. If given, a protected method will be defined with the block's contents. This method typically operates on (calls) the hooks. The private getter method mentioned above can be used to access the hooks. Any block arguments will be used as argument in the method. The method name has the prefix call_ followed by the hook name.

define_hook important_event : ImportantHook do |example|
  important_event_hooks.each &.call(example)
end

# ...

important_event do |example|
  puts "An important event occurred for #{example}"
end