September 26, 2016

Awesome Asciidoctor: Use Captions For Listing Blocks

Asciidoctor has some built-in attributes to work with captions for certain content blocks. For example the table-section attribute defines the caption label (by default Table) that is prefixed to a counter for all tables in the document. When we transform our markup Asciidoctor will insert the text Table followed by the table number. By default the caption for listing blocks is disabled, but we can easily enable it with the listing-caption attribute.

In the following markup we enable the caption for listing blocks and set the value to Listing. This will add the text Listing followed by the listing section counter to the output.

= Code examples
// Enable numbered captions
// for listing blocks.
// We define the constant Listing
// as a caption value. This will be
// followed by a counter.
:listing-caption: Listing

== Creating an application

To create a simple Ratpack application we write
the following code:

.Simple Java Ratpack application
package com.mrhaki;

import ratpack.server.RatpackServer;

public class Main {
    public static void main(String... args) throws Exception {
        RatpackServer.start(server ->
                .handlers(chain ->
                        .get(ctx -> ctx.render("Hello World!"))));

.Simple Groovy Ratpack application
package com.mrhaki

import static ratpack.groovy.Groovy.ratpack

ratpack {
    handlers {
        get {
            render "Hello World!"

When we generate the HTML for this markup we see the caption for the two listing blocks:

To disable the listing captions we must negate the document attribute: :!listing-caption:.

Written with Asciidoctor 1.5.4.