X-Git-Url: https://git.cworth.org/git?a=blobdiff_plain;f=faq.mdwn;h=7e41e961b576e79a6c405d626d5a5937b6869c8d;hb=dcd9cd78af2d41b45b5c53a5f89d0127637098c2;hp=4646ef1a4cface205448bc4607127a2c5a2d1994;hpb=dfd4a6acd5ca705cdf000bbfd22464b5f17f7c7d;p=notmuch-wiki

diff --git a/faq.mdwn b/faq.mdwn
index 4646ef1..7e41e96 100644
--- a/faq.mdwn
+++ b/faq.mdwn
@@ -27,11 +27,26 @@ See [[excluding]].
 
 See help for `message-citation-line-format` for details.
 
+## What are sexp queries?
+
+For the syntax of sexp queries, see [the manual
+page](https://notmuchmail.org/doc/latest/man7/notmuch-sexp-queries.html).
+
+To see if your version of notmuch supports them, run
+
+        $ notmuch config get built_with.sexp_queries
+
 ## How do I search for messages that have no tags?
 
-Unfortunately, there is no way to do this directly.
+To do this directly, you need a recent notmuch compiled with sexp
+queries (see above). You can then run
+
+        $ notmuch search --query=sexp --output=messages '(not (tag *))'
 
-However, it's possible to accomplish this using two searches in shell. First,
+The same style of query should work for any prefix, even user defined
+prefixes like `List` (see below).
+
+Otherwise, it's possible to accomplish this using two searches in shell. First,
 you need to query all tags in the database, and transform the result into a
 query that matches messages that have none of those tags:
 
@@ -44,8 +59,8 @@ Next, use that to query the messages:
 
 ## How do I search for punctuation, specific special characters, or regexp?
 
-Please see the [[notmuch-search-terms manual
-page|manpages/notmuch-search-terms-7]] first.
+Please see the [notmuch-search-terms manual
+page](https://notmuchmail.org/doc/latest/man7/notmuch-search-terms.html) first.
 
 The main thing to understand is that Xapian, and therefore Notmuch, searches are
 closer to natural language searches than regular expression
@@ -54,6 +69,17 @@ searches. Punctuation is mostly ignored.
 The boolean prefix searches (see Boolean and Probabilistic Prefixes in the man
 page), such as tag: or path: searches, need an exact match.
 
+For [specific
+fields](https://notmuchmail.org/doc/latest/man7/notmuch-search-terms.html#search-prefixes)
+it is possible to use regex searches (although these are often
+noticeably slower than native Xapian queries). The limited set of
+fields is a quirk of implementation which requires a Xapian "value
+slot" in the database schema. Adding regex support for more fields to
+would require of adding more value slots to the schema. The
+performance impact of that needs to be experimentally evaluated, and
+assuming it is not too bad, some database upgrade code would need to
+be written.
+
 ## How do I search for folders or paths with spaces?
 
 The spaces in the names must be escaped. For example if you use bash or zsh,
@@ -80,8 +106,8 @@ This is required in order to run the `pre-new` and `post-new` hooks.
 No. Tagging is message based.
 
 It is possible, however, to make tags propagate to all messages in a thread
-using a little bit of scripting in the [[post-new
-hook|manpages/notmuch-hooks-5]]. For example, to add the muted tag to all
+using a little bit of scripting in the [post-new
+hook](https://notmuchmail.org/doc/latest/man5/notmuch-hooks.html). For example, to add the muted tag to all
 messages in threads that have at least one message with the muted tag:
 
         THREAD_TAGS="muted"
@@ -105,17 +131,17 @@ fixed in 1.4.7.  Try reverting Xapian commit
 `093999529acc2f86900d91fed0c7f7af301ab94a`, e.g. with the following
 patch.
 
-[[!format text """
-index 80e578b85..a47f14a68 100644
---- a/xapian-core/backends/glass/glass_postlist.cc
-+++ b/xapian-core/backends/glass/glass_postlist.cc
-@@ -759,7 +759,7 @@ GlassPostList::open_nearby_postlist(const std::string & term_,
-     (void)need_pos;
-     if (term_.empty())
-        RETURN(NULL);
--    if (!this_db.get() || this_db->postlist_table.is_modified())
-+    if (!this_db.get() || this_db->postlist_table.is_writable())
-        RETURN(NULL);
-     RETURN(new GlassPostList(this_db, term_, cursor->clone()));
- }
-"""]]
+
+    index 80e578b85..a47f14a68 100644
+    --- a/xapian-core/backends/glass/glass_postlist.cc
+    +++ b/xapian-core/backends/glass/glass_postlist.cc
+    @@ -759,7 +759,7 @@ GlassPostList::open_nearby_postlist(const std::string & term_,
+         (void)need_pos;
+         if (term_.empty())
+            RETURN(NULL);
+    -    if (!this_db.get() || this_db->postlist_table.is_modified())
+    +    if (!this_db.get() || this_db->postlist_table.is_writable())
+            RETURN(NULL);
+         RETURN(new GlassPostList(this_db, term_, cursor->clone()));
+     }
+