07-29-2009
The more formal term is backreference. A backreference stores the part of the string matched by the part of the regular expression inside the parentheses.
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LEARN ABOUT SUSE
mail::spamassassin::plugin::replacetags
Mail::SpamAssassin::Plugin::ReplaceTags(3) User Contributed Perl Documentation Mail::SpamAssassin::Plugin::ReplaceTags(3)
NAME
Mail::SpamAssassin::Plugin::ReplaceTags - tags for SpamAssassin rules
The plugin allows rules to contain regular expression tags to be used in regular expression rules. The tags make it much easier to
maintain complicated rules.
Warning: This plugin relies on data structures specific to this version of SpamAssasin; it is not guaranteed to work with other versions of
SpamAssassin.
SYNOPSIS
loadplugin Mail::SpamAssassin::Plugin::ReplaceTags
replace_start <
replace_end >
replace_tag A [a@]
replace_tag G [gk]
replace_tag I [il|!1y?xccxcdxcexcfxecxedxeexef]
replace_tag R [r3]
replace_tag V (?:[vu]|\/)
replace_tag SP [s~_-]
body VIAGRA_OBFU /(?!viagra)<V>+<SP>*<I>+<SP>*<A>+<SP>*<G>+<SP>*<R>+<SP>*<A>+/i
describe VIAGRA_OBFU Attempt to obfuscate "viagra"
replace_rules VIAGRA_OBFU
RULE DEFINITIONS AND PRIVILEGED SETTINGS
replace_tag tagname expression
Assign a valid regular expression to tagname.
Note: It is not recommended to put quantifiers inside the tag, it's better to put them inside the rule itself for greater flexibility.
replace_pre tagname expression
Assign a valid regular expression to tagname. The expression will be placed before each tag that is replaced.
replace_inter tagname expression
Assign a valid regular expression to tagname. The expression will be placed between each two immediately adjacent tags that are
replaced.
replace_post tagname expression
Assign a valid regular expression to tagname. The expression will be placed after each tag that is replaced.
replace_rules list_of_tests
Specify a list of symbolic test names (separated by whitespace) of tests which should be modified using replacement tags. Only simple
regular expression body, header, uri, full, rawbody tests are supported.
replace_start string
replace_end string
String(s) which indicate the start and end of a tag inside a rule. Only tags enclosed by the start and end strings are found and
replaced.
perl v5.12.1 2010-03-16 Mail::SpamAssassin::Plugin::ReplaceTags(3)