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By default all promises are made in the default namespace. Specifying a namespace places the bundle or body in a different namespace to allow re-use of common names. Using namespaces makes it easier to share and consume policy from other authors.

Like bundle names and classes, namespaces may only contain alphanumeric and underscore characters (a-zA-Z0-9_).

Declaration

Namespaces are declared with [body file control][file control#namespace]. A namespace applies within a single file to all subsequently defined bodies and bundles following the namespace declaration until a different namespace has been declared or until the end of the file.

[%CFEngine_include_example(namespace_declaration.cf)%]

Notes:

  • Multiple namespaces can be declared within the same file
  • The same namespace can be declared in multiple files
  • The same namespace can be declared in the same file multiple times

Methods|usebundle

Methods promises assume you are referring to a bundle in the same namespace as the promiser. To refer to a bundle in another namespace you must specify the namespace by prefixing the bundle name with the namespace followed by a colon (:).

[%CFEngine_include_example(namespace_methods-usebundle.cf)%]

Bodies

Bodies are assumed to be within the same namespace as the promiser. To use a body from another namespace the namespace must be specified by prefixing the body name with the namespace followed by a colon (:).

A common mistake is forgetting to specify default: when using bodies from the standard library which resides in the default namespace.

[%CFEngine_include_example(namespace_bodies.cf)%]

Variables

Variables (except for [Special variables][Special variables]) are assumed to be within the same scope as the promiser but can also be referenced fully qualified with the namespace.

[%CFEngine_include_example(namespace_variable_references.cf)%]

[Special variables][Special variables] are always accessible without a namespace prefix. For example, this, mon, sys, and const fall in this category.

[%CFEngine_include_example(namespace_special_var_exception.cf)%]

Notes:

  • The [variables Augments key][Augments#variables] defines variables in the main bundle of the data namespace by default but supports seeding variable values in any specified namespace.

Classes

Promises can only define classes within the current namespace. Classes are understood to refer to classes in the current namespace if a namespace is not specified (except for Hard classes). To refer to a class in a different namespace prefix the class with the namespace suffixed by a colon (:).

[%CFEngine_include_example(namespace_classes.cf)%]

[Hard classes][Classes and decisions#Hard classes] exist in all namespaces and thus can be referred to from any namespace without qualification.

[%CFEngine_include_example(namespace_hard_classes.cf)%]