DocBook 5.2: The Definitive Guide  (Version 5.2.6 for DocBook 5.2b09a)

V5.2unionsynopsis

unionsynopsis — The syntax summary for a union-of-types definition.

Synopsis

unionsynopsis ::= [-]

Attributes

Common attributes and common linking attributes.

Additional attributes:

  • language
  • ordered (enumeration)
    • “0”
    • “1”

Additional Constraints

  • If this element is the root element, it must have a version attribute.

Description

A unionsynopsis contains the syntax summary of a union (generally speaking, unions programming language sense).

This is one of the few places where DocBook attempts to model as well as describe. The content model of unionsynopsis was designed to capture a wide range of semantics.

Processing expectations

Formatted inline.

Attributes

Common attributes and common linking attributes.

language

Identifies the language (i.e. programming language) of the content.

ordered

Indicates how the value of a union is specified.

Enumerated values:
“0”

Value of enum is specified explicitly using enumvalue

“1”

Value of enum is inferred from its position

Examples

<article xmlns:db="http://docbook.org/ns/docbook"
         xmlns:xlink="http://www.w3.org/1999/xlink"
         version="5.2">
   <info>
      <title>Julia unions</title>
      <abstract>
         <para>Model the following construct: <code>IntOrString = Union{Int,AbstractString}</code></para>
      </abstract>
   </info>
   <unionsynopsis>
     <union>
       <unionname>IntOrString</unionname>
       <type>Int</type>
       <type>AbstractString</type>
     </union>
   </unionsynopsis>
</article>
<unionsynopsis>
<union>
<unionname>IntOrString</unionname>
<type>Int</type>
<type>AbstractString</type>
</union>
</unionsynopsis>