1 Overview
1.1 Background
DocBuilder has been used within the OTP project to generate documentation for Erlang/OTP itself for more than ten years. It has now been released as a regular Erlang/OTP application.
The intention with DocBuilder is that it should be as easy to use and maintain as possible and generate adequate documentation for OTP's needs. It uses frames, which can probably be regarded as old-fashioned today. Hopefully, this should be improved in the future.
Originally, DocBuilder input was SGML files and external tools was used for parsing. The internal version used in the OTP project can generate not only HTML code but also LaTeX (for PDF and PostScript) and nroff (for UNIX man pages). (Again, using external tools). Because of this, the parsed source code is transformed into a tree structure before being transformed again into the desired format.
1.2 DTD Suite
Input is written as XML according to one of the DTDs and output is corresponding HTML. Documentation for an Erlang/OTP application is usually organized as follows:
- User's Guide
- Reference Manual
-
(DTD: application A collection of manual pages for modules (erlref), applications (appref), commands (comref), C libraries (cref) and files (fileref).
- Release Notes
-
Same structure as the User's Guide.
In some cases, one or more of the User's Guide, Reference Manual and Release Notes are omitted. Also, it is possible to use either the application or part DTD to write other types of documentation for the application.
A special kind of DTD, fascicules, can be used to specify the different parts of the documentation, and which one of those should be shown as default.
1.3 Structure of Generated HTML
The generated HTML corresponding to a part or application document is split into a left frame and a right frame. The left frame contains information about the document and links to the included files, that is chapters or manual pages. The right frame is used to display either the front page for the document, or the selected chapter/manual page.
The left frame also contains links to a bibliography and a glossary, which are automatically generated.
In the case of an application document, the left frame also contains a link to an automatically generated index.
1.4 Basic Tags
All DTDs in the DocBuilder DTD suite share a basic set of tags. An author can easily switch from one DTD to another and still use the same basic tags. It is furthermore easy to copy pieces of information from one document to another, even though they do not use the same DTD.
The basic set of tags are divided into two categories: block tags and inline tags. Block tags typically define a separate block of information, like a paragraph or a list. Inline tags are typically used within block tags, for example a highlighted word within a paragraph.
1.5 About This Document
In this User's Guide, the structure of the different documents and the meaning of the tags are explained. There are numerous examples of documentation source code.
For readability and simplicity, the examples have been kept as short as possible. For an example of what the generated HTML will look like, it is recommended to look at the DocBuilder documentation itself:
- This User's Guide is written using the part and chapter DTDs.
- The Reference Manual is written using the application, appref and erlref DTDs.
1.6 Usage
-
Create the relevant XML files.
If there are EDoc comments in a module, the function docb_gen:module/1,2 can be used to generate an XML file according to the erlref DTD for this module.
-
The XML files can be validated using docb_xml_check:validate/1.
-
Generate HTML files by using docb_transform:file/1,2.