Calling Templates

You can call a template from a generated file or from another template by entering its name surrounded by percentage signs. Object properties, collections, and local and global variables are called in the same way. At generation time, a template call is replaced by the template content, which is then resolved to its final textual value.

Examples:

%Name% - Calls the object's Name property
%myTemplate% - Calls the %myTemplate% template
%CurrentDate% - Calls the %CurrentDate% global variable (see Accessing Global Variables)

Breaking templates into concise units and calling them at generation time helps with readability and reuse. For example, you can define a commonly-used condition in one template and reference it in multiple other templates:

Example
The `%isInner%` template is defined as: .bool (%ContainerClassifier%!=null) The `%QualifiedCode%` template calls the `%isInner%` template to test if the class is an inner class: .if (%isInner%) %ContainerClassifier.QualifiedCode%::%Code% .else %Code% .endif Result: C2::C1 The `%QualifiedCode%` template is applied to the `C1` class, which is an inner class to `C2`.

Inheritance and Polymorphism
Templates are defined on a particular metaclass in a language definition file or extension and are inherited by and available to the children of the metaclass. For example, a template defined on the Classifier metaclass is available to templates or generated files defined on the Class and Interface metaclasses.
Passing Parameters to a Template
You can pass parameters to a template, using the syntax:%t(p1,p2...)%.
Recursive Templates
A template can call itself, but such a template should contain some kind of criteria or scope change to avoid an infinite loop.

Parent topic: Customizing Generation with GTL