////
Included in:

- user-manual: Extensions: Block processor example
////

Purpose::
  Register a custom block style named `shout` that uppercases all the words and converts periods to exclamation points.

.sample-with-shout-block.adoc

```
[shout]
The time is now. Get a move on.
```

.ShoutBlock

```ruby
require 'asciidoctor'
require 'asciidoctor/extensions'

class ShoutBlock < Asciidoctor::Extensions::BlockProcessor
  PeriodRx = /\.(?= |$)/

  use_dsl

  named :shout
  on_context :paragraph
  name_positional_attributes 'vol'
  parse_content_as :simple

  def process parent, reader, attrs
    volume = ((attrs.delete 'vol') || 1).to_i
    create_paragraph parent, (reader.lines.map {|l| l.upcase.gsub PeriodRx, '!' * volume }), attrs
  end
end
```

.Usage

```ruby
Asciidoctor::Extensions.register do
  block ShoutBlock
end

Asciidoctor.convert_file 'sample-with-shout-block.adoc', :safe => :safe
```