Sieve regex extension

As of MS 6.1, the MTA supports the proposed Sieve " " extension (see ), which adds a " " match type to the Sieve language. The capability name is " ": require "regex"; Because evaluating arbitrary regex expressions is potentially computationally expensive, whether -- and which -- Sieves may use " " may be controlled with the   MTA option; the default is , meaning that " " is supported in all Sieves.

Restrictions on " ": Note that " " is not supported with the " " test (from the  " " extension). Another restriction is that utf-8 comparator  use with " " is not supported. For performance reasons, the " " match type is not supported for use with the Sieve " " test.

New in 8.0, Sieve " " match type tests now set variables in the same way that " " match type tests do. Note that unlike glob-style matches (as when " " is used) where the default is to store whatever matched any wildcard that appears in the pattern, in regex match type tests only those regular expressions enclosed in parentheses are stored. If parentheses are needed but storage is not desired, then the " " form may be used.

See also:
 * enable_sieve_regex MTA Option
 * Sieve language extension MTA options
 * Sieve imap4flags extension
 * Sieve comparators
 * Sieve body extension
 * Sieve importance extension
 * Sieve variables extension
 * Sieve supported extensions
 * Sieve filters