h1. Pattern

This is the most widely used _Extension Node_.

The corresponding tree is entered if extension that is called (or entered) by the caller matches the configured pattern. Initially _Pattern Extension_ Node has pattern of "_X.". This pattern matches any digit.

There can be several _Pattern Extension_ entrance points for particular [[Call Handler]]. In case if there several _Pattern Extension_ Nodes, each of them must be assigned a priority. Initial priority is 0. The node with greater priority will be checked before the node with smaller one.