ifndef

The ifndef command creates a sort of pre-processing behavior. The code inside the if node is parsed at scripting loading time only if the referenced define doesn't exist.

A typical usage is to create script files that can be referenced by multiple other files.

Platform support

This element is fully supported on XR-Windows, XR-Portable Windows, XR-Portable iOS, XR-Portable Android, and XR-P WASM platforms.

To configure an Ifndef

1. Create an ifndef that references the define created in the first row.

2. Put all the scripts inside the ifndef element.

3. Create a define in the last script row inside ifndef.

In this way, the script nodes are read only during the first inclusion of the file.

Code example

This is a code example for the ifndef node.

<ifndef name="template">

<deftemplate name="aTemplate" >

<!--...-->

</deftemplate>

<define name="template" />

</ifndef>

Position

The ifndef element must be inside a context node, such as Context or Global.

Fields

These are the fields for ifndef command.