Data types

The data type system in Puppet 4 allows you to check and verify whether a variable is of a specific data type. This prevents code from behaving incorrectly when (for example) it expects an array but receives a Boolean value.

The full power of data types will be explained in Chapter 7, New Features from Puppet 4 and 5. Within Puppet manifests, it is possible to check for data types using the regexp control structure.

Puppet has core data types and abstract data types. The core data types are the most commonly used types of data, such as string or integer, whereas abstract data types allow for more sophisticated type validation, such as optional or variant.

Prior to dealing with data types, we must understand the concept of control structures within Puppet manifests.