doc: add more information on operators.

[notmuch] / doc / man7 / notmuch-search-terms.rst

diff --git a/doc/man7/notmuch-search-terms.rst b/doc/man7/notmuch-search-terms.rst
index 54138d230f0b8559d48fcda20b5129f882738815..2ad100cf5f075a34c10d191033647d5242e8e232 100644 (file)
--- a/doc/man7/notmuch-search-terms.rst
+++ b/doc/man7/notmuch-search-terms.rst
@@ -124,16 +124,75 @@ The time range can also be specified using timestamps with a syntax of:
 Each timestamp is a number representing the number of seconds since
 1970-01-01 00:00:00 UTC.
 
+Operators
+---------
+
 In addition to individual terms, multiple terms can be combined with
-Boolean operators ( **and**, **or**, **not** , etc.). Each term in the
-query will be implicitly connected by a logical AND if no explicit
-operator is provided, (except that terms with a common prefix will be
-implicitly combined with OR until we get Xapian defect #402 fixed).
-
-Parentheses can also be used to control the combination of the Boolean
-operators, but will have to be protected from interpretation by the
-shell, (such as by putting quotation marks around any parenthesized
-expression).
+Boolean operators (**and**, **or**, **not**, and **xor**). Each term
+in the query will be implicitly connected by a logical AND if no
+explicit operator is provided (except that terms with a common prefix
+will be implicitly combined with OR).  The shorthand '-<term>' can be
+used for 'not <term>' but unfortunately this does not work at the
+start of an expression.  Parentheses can also be used to control the
+combination of the Boolean operators, but will have to be protected
+from interpretation by the shell, (such as by putting quotation marks
+around any parenthesized expression).
+
+In addition to the standard boolean operators, Xapian provides several
+operators specific to text searching.
+
+::
+
+        notmuch search term1 NEAR term2
+
+will return results where term1 is within 10 words of term2. The
+threshold can be set like this:
+
+::
+
+        notmuch search term1 NEAR/2 term2
+
+The search
+
+::
+
+        notmuch search term1 ADJ term2
+
+will return results where term1 is within 10 words of term2, but in the
+same order as in the query. The threshold can be set the same as with
+NEAR:
+
+::
+
+        notmuch search term1 ADJ/7 term2
+
+
+Stemming
+--------
+
+**Stemming** in notmuch means that these searches
+
+::
+
+        notmuch search detailed
+        notmuch search details
+        notmuch search detail
+
+will all return identical results, because Xapian first "reduces" the
+term to the common stem (here 'detail') and then performs the search.
+
+There are two ways to turn this off: a search for a capitalized word
+will be performed unstemmed, so that one can search for "John" and not
+get results for "Johnson"; phrase searches are also unstemmed (see
+below for details).  Stemming is currently only supported for
+English. Searches for words in other languages will be performed unstemmed.
+
+Wildcards
+---------
+
+It is possible to use a trailing '\*' as a wildcard. A search for
+'wildc\*' will match 'wildcard', 'wildcat', etc.
+
 
 Boolean and Probabilistic Prefixes
 ----------------------------------