protected property ImmutableInvalidationBase::$expression in Purge 8.3

Mixed expression (or NULL) that describes what needs to be invalidated.

Type: mixed|null

File

src/Plugin/Purge/Invalidation/ImmutableInvalidationBase.php, line 36

Class

ImmutableInvalidationBase

Provides base implementations the immutable invalidation object.

Namespace

Drupal\purge\Plugin\Purge\Invalidation

Code

protected $expression = NULL;