To be inserted into TSref, as the first chapter just after the Introduction.
TypoScript templates structure
A TypoScript ("TS") template has two parts: the actual script (this is called the TypoScript "setup") and TypoScript constants. This is described in further detail in doc_core_ts. It can also include other TS templates from various sources. Lastly it can reference external files containing TS.
This flexible but complex architecture can make it hard to get an overview of an actual template structure. To help with this, TYPO3 provides some useful tools.
A good practice to maintain templates is to create libraries of TypoScript code in a template and then include that template in another one to reuse the code. This is the point of static templates.
Elements of a template
As said above, a TypoScript template is divided into constants and setup. The constants are simple values meant that can be substituted inside the setup part. Constants are generally defined either to emphasize some important values or to provide a single definition for values that are used in multiple places. The setup part is the actual template.
Constants are described in more depth in "TypoScript Syntax and In-depth Study" (extension: doc_core_ts).
A template can also call on other templates of two kinds: so called "static" templates and "basis" templates. Static templates are predefined by the TYPO3 core or by extensions. Those provided by the core are stored in the table static_templates. They can be included from the "Include static" field (see screenshot below). Static templates may also be provided by extensions. They are selected in the "Include static (from extensions)" field.
Basis templates are just usual template records, included into other template records. They make it possible to split your TypoScript into smaller chunks to be included as needed.
Both the constants and the setup fields can refer to an external file containing TypoScript by using the <INCLUDE_TYPOSCRIPT> directive. An example:
<INCLUDE_TYPOSCRIPT: source="FILE: fileadmin/typoscript.ts">
More details about<INCLUDE_TYPOSCRIPT> can be found "TypoScript Syntax and In-depth Study" (extension: doc_core_ts).
The Web > Template module contains four tools that can greatly help with the creation and management of TypoScript templates. They are described hereafter.
TypoScript Object Browser