Example: How the @cascade
attribute functions
The following example illustrates how the @cascade
attribute can be used
to fine tune how the values for the @platform
attribute apply to topics referenced
in a DITA map.
Here a DITA map contains a collection of topics that apply to Windows, Linux, and Macintosh OS; it also contains a topic that is only applicable to users running the application on Linux.
<map product="PuffinTracker" platform="win linux mac" cascade="nomerge">
<title>Puffin Tracking Software</title>
<topicref href="intro.dita" navtitle="Introduction"/>
<topicref href="setup.dita" navtitle="Setting up the product"/>
<topicref href="linux-instructions.dita" navtitle="Linux instructions" platform="linux"/>
</map>
The values of the @platform
attribute set at the map level cascade throughout
the map and apply to the "Introduction" and "Setting up the product" topics. However, since the
value of the @cascade
attribute is set to "nomerge", the value of the
@platform
attribute for the "Linux instructions" topic does not merge with the
values that cascade from above in the DITA map. The effective value of the
@platform
attribute for linux-instructions.dita is
"linux".
The same results are produced by the following mark-up:
<map product="PuffinTracker" platform="win linux mac">
<title>Puffin Tracking Software</title>
<topicref href="intro.dita" navtitle="Introduction"/>
<topicref href="setup.dita" navtitle="Setting up the product"/>
<topicref href="linux-instructions.dita" navtitle="Linux instructions" platform="linux" cascade="nomerge"/>
</map>