From 6cb0284cc3fe66c4c20a09a651ba897ed6e2f71e Mon Sep 17 00:00:00 2001 From: Kaz Kylheku Date: Fri, 23 Sep 2016 06:38:58 -0700 Subject: doc: add regex intro paragraph. * txr.1: New paragraph added under the Regular Expressions Library minor section. --- txr.1 | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/txr.1 b/txr.1 index 91b1a4a0..e049b259 100644 --- a/txr.1 +++ b/txr.1 @@ -31724,6 +31724,19 @@ non-deterministically: .cble .SS* Regular Expression Library + +\*(TX provides a "pure" regular expression implementation based on automata +theory, which equates regular expressions, finite automata and sets of strings. +A regular expression determines whether or not a string of input characters +belongs to a set. \*(TX regular expressions do not support features such +as as "anchoring" a match to the start or end of a string, or capture of +parenthesized sub-expression matches into registers. Parenthesis syntax +denotes only grouping, with no additional meaning. + +The semantics of whether a regular expression is used for a substring +search, prefix match, suffix match, spring splitting and so forth comes from +the functions which use regular expressions to perform these operations. + .NP* Regular Expressions as Functions .synb .mets >> [ regex >> [ start <> [ from-end ]] < string ] -- cgit v1.2.3