Remove \s TODO: these are intelligently ignored along with \m and \M.

[mandoc.git] / mdoc.3

diff --git a/mdoc.3 b/mdoc.3
index 17d41fefe4164e3c759d9446b525bff98b7d95ac..b141eeaa32c7da114ffbf72ec3053f5edcdbbfa1 100644 (file)
--- a/mdoc.3
+++ b/mdoc.3
@@ -1,6 +1,7 @@
-.\"    $Id: mdoc.3,v 1.43 2010/06/27 15:52:41 kristaps Exp $
+.\"    $Id: mdoc.3,v 1.48 2010/07/07 15:04:54 kristaps Exp $
 .\"
-.\" Copyright (c) 2009-2010 Kristaps Dzonsons <kristaps@bsd.lv>
+.\" Copyright (c) 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
+.\" Copyright (c) 2010 Ingo Schwarze <schwarze@openbsd.org>
 .\"
 .\" Permission to use, copy, modify, and distribute this software for any
 .\" purpose with or without fee is hereby granted, provided that the above
@@ -14,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: June 27 2010 $
+.Dd $Mdocdate: July 7 2010 $
 .Dt MDOC 3
 .Os
 .Sh NAME
@@ -29,13 +30,12 @@
 .Nd mdoc macro compiler library
 .Sh SYNOPSIS
 .In mandoc.h
-.In regs.h
 .In mdoc.h
 .Vt extern const char * const * mdoc_macronames;
 .Vt extern const char * const * mdoc_argnames;
 .Ft "struct mdoc *"
 .Fo mdoc_alloc
-.Fa "const struct regset *regs"
+.Fa "struct regset *regs"
 .Fa "void *data"
 .Fa "int pflags"
 .Fa "mandocmsg msgs"
@@ -217,10 +217,14 @@ and
 fields), its position in the tree (the
 .Va parent ,
 .Va child ,
+.Va nchild ,
 .Va next
 and
 .Va prev
-fields) and some type-specific data.
+fields) and some type-specific data, in particular, for nodes generated
+from macros, the generating macro in the
+.Va tok
+field.
 .Pp
 The tree itself is arranged according to the following normal form,
 where capitalised non-terminals represent nodes.
@@ -235,11 +239,11 @@ where capitalised non-terminals represent nodes.
 .It ELEMENT
 \(<- TEXT*
 .It HEAD
-\(<- mnode+
+\(<- mnode*
 .It BODY
-\(<- mnode+
+\(<- mnode* [ENDBODY mnode*]
 .It TAIL
-\(<- mnode+
+\(<- mnode*
 .It TEXT
 \(<- [[:printable:],0x1e]*
 .El
@@ -253,20 +257,88 @@ an empty line will produce a zero-length string.
 Multiple body parts are only found in invocations of
 .Sq \&Bl \-column ,
 where a new body introduces a new phrase.
+.Ss Badly-nested Blocks
+The ENDBODY node is available to end the formatting associated
+with a given block before the physical end of that block.
+It has a non-null
+.Va end
+field, is of the BODY
+.Va type ,
+has the same
+.Va tok
+as the BLOCK it is ending, and has a
+.Va pending
+field pointing to that BLOCK's BODY node.
+It is an indirect child of that BODY node
+and has no children of its own.
+.Pp
+An ENDBODY node is generated when a block ends while one of its child
+blocks is still open, like in the following example:
+.Bd -literal -offset indent
+\&.Ao ao
+\&.Bo bo ac
+\&.Ac bc
+\&.Bc end
+.Ed
+.Pp
+This example results in the following block structure:
+.Bd -literal -offset indent
+BLOCK Ao
+       HEAD Ao
+       BODY Ao
+               TEXT ao
+               BLOCK Bo, pending -> Ao
+                       HEAD Bo
+                       BODY Bo
+                               TEXT bo
+                               TEXT ac
+                               ENDBODY Ao, pending -> Ao
+                               TEXT bc
+TEXT end
+.Ed
+.Pp
+Here, the formatting of the
+.Sq \&Ao
+block extends from TEXT ao to TEXT ac,
+while the formatting of the
+.Sq \&Bo
+block extends from TEXT bo to TEXT bc.
+It renders as follows in
+.Fl T Ns Cm ascii
+mode:
+.Pp
+.Dl <ao [bo ac> bc] end
+.Pp
+Support for badly-nested blocks is only provided for backward
+compatibility with some older
+.Xr mdoc 7
+implementations.
+Using badly-nested blocks is
+.Em strongly discouraged :
+the
+.Fl T Ns Cm html
+and
+.Fl T Ns Cm xhtml
+front-ends are unable to render them in any meaningful way.
+Furthermore, behaviour when encountering badly-nested blocks is not
+consistent across troff implementations, especially when using  multiple
+levels of badly-nested blocks.
 .Sh EXAMPLES
 The following example reads lines from stdin and parses them, operating
 on the finished parse tree with
 .Fn parsed .
 This example does not error-check nor free memory upon failure.
 .Bd -literal -offset indent
+struct regset regs;
 struct mdoc *mdoc;
 const struct mdoc_node *node;
 char *buf;
 size_t len;
 int line;
 
+bzero(&regs, sizeof(struct regset));
 line = 1;
-mdoc = mdoc_alloc(NULL, 0, NULL);
+mdoc = mdoc_alloc(&regs, NULL, 0, NULL);
 buf = NULL;
 alloc_len = 0;