Regular Expressions

Regular expressions are a formal language used for text search. Basically, it is a pattern-line setting a search rule.

The following parameters are used to create a filter:


Type a phrase in the text of a filter. The rule will apply for a message containing a fully identical line.


You can use the regular expression language in the text of a filter. If you are familiar with the regular expression language, you may create some custom filters with more complex search parameters.


The “plain” rule will apply only if a message contains the phrase “How does a plain filter work?”, and will not apply to any other cases. If at least one symbol is removed or replaced, the message will not be identified. The “custom” rule is the simplest example of a regular expressions search; this rule will apply to any message containing at least one figure.