Types of Component

An ItemDefinition element can be defined as a tree of components that consists of only one of either:

• A built-in type or

• A Composition of ItemDefinition elements

In this tree of components, if a component is a 'leaf' that has no child components, it must be set as a built-in type. If an ItemDefinition has child components, it is those child/leaf components that are set as a built-in type.

For example Applicant Data and Monthly are compositions, whereas Age and Expenses are leaves set to a built-in type:

The FEEL language has these built-in types:

• number
• string
• boolean
• days and time duration
• years and months duration
• time
• date and time

Note: 'number', 'string' and 'boolean' are supported by Enterprise Architect for simulation.

To set a type for a 'leaf' ItemDefinition, you can use one of three methods:

• Select  the appropriate context menu option in the DMN Expression window (Recommended)
  
• Type ': string', ': boolean' or ': number' after the name in the cell in the DMN Expression window
• Type 'string', 'boolean' or 'number' as the value of the tag 'Type' in the Properties window for the ItemDefinition

For composite ItemDefinitions, the context menu also offers options to create a child or a sibling component, or to delete the selected item: