*** empty log message ***

4 files changed, 264 insertions, 190 deletions

diff --git a/macro.c b/macro.c
index 79497bbf..c59e5ec3 100644
--- a/macro.c
+++ b/macro.c
@@ -1,4 +1,4 @@
-/* $Id: macro.c,v 1.17 2009/01/02 14:06:16 kristaps Exp $ */
+/* $Id: macro.c,v 1.18 2009/01/03 18:38:39 kristaps Exp $ */
 /*
  * Copyright (c) 2008 Kristaps Dzonsons <kristaps@kth.se>
  *
@@ -171,6 +171,9 @@ append_text(struct mdoc *mdoc, int tok,
 		return(0);
 
 	switch (tok) {
+		/*
+		 * FIXME: deprecate this "feature" of mdoc(7).
+		 */
 	case (MDOC_At):
 		if (0 == sz)
 			break;
@@ -210,6 +213,7 @@ macro_text(MACRO_PROT_ARGS)
 	/* Token pre-processing.  */
 
 	switch (tok) {
+		/* FIXME: move to validate.c. */
 	case (MDOC_Pp):
 		/* `.Pp' ignored when following `.Sh' or `.Ss'. */
 		assert(mdoc->last);
@@ -349,6 +353,8 @@ macro_close_explicit(MACRO_PROT_ARGS)
 		/* NOTREACHED */
 	}
 
+	if (0 != buf[*pos])
+		return(mdoc_err(mdoc, tok, ppos, ERR_ARGS_EQ0));
 	return(scope_rewind_exp(mdoc, ppos, tok, tt));
 }
 
@@ -465,17 +471,19 @@ macro_scoped(MACRO_PROT_ARGS)
 
 	mdoc_argv_free(argc, argv);
 
-	mdoc_head_alloc(mdoc, ppos, tok);
-	mdoc->next = MDOC_NEXT_CHILD;
-
-	for (i = 0; i < sz; i++) {
-		mdoc_word_alloc(mdoc, ppos, args[i]);
-		mdoc->next = MDOC_NEXT_SIBLING;
+	if (sz > 0) {
+		mdoc_head_alloc(mdoc, ppos, tok);
+		mdoc->next = MDOC_NEXT_CHILD;
+	
+		for (i = 0; i < sz; i++) {
+			mdoc_word_alloc(mdoc, ppos, args[i]);
+			mdoc->next = MDOC_NEXT_SIBLING;
+		}
+	
+		if ( ! scope_rewind_line(mdoc, ppos, tok))
+			return(0);
 	}
 
-	if ( ! scope_rewind_line(mdoc, ppos, tok))
-		return(0);
-
 	mdoc_body_alloc(mdoc, ppos, tok);
 	mdoc->next = MDOC_NEXT_CHILD;
 
diff --git a/mdoc.h b/mdoc.h
index f485db81..7301217b 100644
--- a/mdoc.h
+++ b/mdoc.h
@@ -1,4 +1,4 @@
-/* $Id: mdoc.h,v 1.12 2009/01/02 14:06:16 kristaps Exp $ */
+/* $Id: mdoc.h,v 1.13 2009/01/03 18:38:39 kristaps Exp $ */
 /*
  * Copyright (c) 2008 Kristaps Dzonsons <kristaps@kth.se>
  *
@@ -218,7 +218,10 @@ enum 	mdoc_err {
 	ERR_ARGS_GE1,
 	ERR_ARGS_LE2,
 	ERR_ARGS_MANY,
-	ERR_CHILD_HEAD
+	ERR_SYNTAX_CHILDHEAD,
+	ERR_SYNTAX_CHILDBODY,
+	ERR_SYNTAX_EMPTYBODY,
+	ERR_SYNTAX_EMPTYHEAD
 };
 
 enum	mdoc_att {
@@ -242,6 +245,7 @@ enum	mdoc_warn {
 	WARN_SYNTAX_MACLIKE,
 	WARN_SYNTAX_ARGLIKE,
 	WARN_SYNTAX_QUOTED,
+	WARN_SYNTAX_EMPTYBODY,
 	WARN_IGN_AFTER_BLK,
 	WARN_IGN_BEFORE_BLK,
 	WARN_IGN_OBSOLETE,
diff --git a/mdocml.c b/mdocml.c
index 57932a93..d2fe92c6 100644
--- a/mdocml.c
+++ b/mdocml.c
@@ -1,4 +1,4 @@
-/* $Id: mdocml.c,v 1.31 2009/01/01 20:40:16 kristaps Exp $ */
+/* $Id: mdocml.c,v 1.32 2009/01/03 18:38:39 kristaps Exp $ */
 /*
  * Copyright (c) 2008 Kristaps Dzonsons <kristaps@kth.se>
  *
@@ -398,8 +398,17 @@ msg_err(void *arg, int tok, int col, enum mdoc_err type)
 	case (ERR_SYNTAX_ARGMANY):
 		lit = "syntax: too many values for macro argument";
 		break;
-	case (ERR_CHILD_HEAD):
-		lit = "scope context expects block-header child";
+	case (ERR_SYNTAX_CHILDHEAD):
+		lit = "syntax: expected only block-header section";
+		break;
+	case (ERR_SYNTAX_CHILDBODY):
+		lit = "syntax: expected only a block-body section";
+		break;
+	case (ERR_SYNTAX_EMPTYHEAD):
+		lit = "syntax: block-header section may not be empty";
+		break;
+	case (ERR_SYNTAX_EMPTYBODY):
+		lit = "syntax: block-body section may not be empty";
 		break;
 	default:
 		abort();
@@ -489,6 +498,9 @@ msg_warn(void *arg, int tok, int col, enum mdoc_warn type)
 	case (WARN_SYNTAX_ARGLIKE):
 		lit = "syntax: argument-like value";
 		break;
+	case (WARN_SYNTAX_EMPTYBODY):
+		lit = "syntax: empty block-body section";
+		break;
 	case (WARN_SEC_OO):
 		lit = "section is out of conventional order";
 		break;
diff --git a/validate.c b/validate.c
index 3d1c3687..9088af51 100644
--- a/validate.c
+++ b/validate.c
@@ -1,4 +1,4 @@
-/* $Id: validate.c,v 1.13 2009/01/02 14:06:16 kristaps Exp $ */
+/* $Id: validate.c,v 1.14 2009/01/03 18:38:39 kristaps Exp $ */
 /*
  * Copyright (c) 2008 Kristaps Dzonsons <kristaps@kth.se>
  *
@@ -24,12 +24,19 @@
 /* FIXME: `.St' can only have one argument set. */
 
 typedef int	(*v_args_sz)(struct mdoc *, int, int, int);
-typedef int	(*v_args)(struct mdoc *, int, int, int, 
-			const char *[], int, const struct mdoc_arg *);
-typedef int	(*v_post)(struct mdoc *, int, int);
+typedef int	(*v_args)(struct mdoc *, int, int, 
+			int, const char *[],
+			int, const struct mdoc_arg *);
+typedef int	(*v_tree)(struct mdoc *, int, int);
+
+
+struct	valids {
+	v_args_sz sz;
+	v_args	  args;
+	v_tree	  tree_pre;
+	v_tree	  tree_post;
+};
 
-static	int	  need_head_child(struct mdoc *, int, int);
-static	int	  no_head_child(struct mdoc *, int, int);
 
 static	int	  assert_eq0(struct mdoc *, int, int, int);
 static	int	  assert_le1(struct mdoc *, int, int, int);
@@ -40,138 +47,137 @@ static	int	  need_le2(struct mdoc *, int, int, int);
 static	int	  want_eq0(struct mdoc *, int, int, int);
 static	int	  want_ge1(struct mdoc *, int, int, int);
 
-static	int	  args_ref(struct mdoc *, int, int, int, 
-			const char *[], int, const struct mdoc_arg *);
-static	int	  args_bool(struct mdoc *, int, int, int, 
-			const char *[], int, const struct mdoc_arg *);
-static	int	  args_Sh(struct mdoc *, int, int, int, 
-			const char *[], int, const struct mdoc_arg *);
-static	int	  args_blocknest(struct mdoc *, int, int, int, 
-			const char *[], int, const struct mdoc_arg *);
-static	int	  args_At(struct mdoc *, int, int, int, 
-			const char *[], int, const struct mdoc_arg *);
-static	int	  args_Xr(struct mdoc *, int, int, int, 
-			const char *[], int, const struct mdoc_arg *);
-
-struct	valids {
-	v_args_sz sz;
-	v_args	  args;
-	v_post	  post;
-};
-
+static	int	  tree_pre_ref(struct mdoc *, int, int);
+static	int	  tree_pre_display(struct mdoc *, int, int);
+
+static	int	  tree_post_onlyhead(struct mdoc *, int, int);
+static	int	  tree_post_onlybody(struct mdoc *, int, int);
+static	int	  tree_post_warnemptybody(struct mdoc *, int, int);
+
+static	int	  args_bool(struct mdoc *, int, int, 
+			int, const char *[], 
+			int, const struct mdoc_arg *);
+static	int	  args_sh(struct mdoc *, int, int, 
+			int, const char *[], 
+			int, const struct mdoc_arg *);
+static	int	  args_an(struct mdoc *, int, int, 
+			int, const char *[], 
+			int, const struct mdoc_arg *);
+static	int	  args_nopunct(struct mdoc *, int, int, 
+			int, const char *[], 
+			int, const struct mdoc_arg *);
+static	int	  args_xr(struct mdoc *, int, int, 
+			int, const char *[], 
+			int, const struct mdoc_arg *);
 
-/* 
- * FIXME: have arrays of function pointers in case we want multiple
- * check callbacks per macro.
- */
 
 const	struct valids mdoc_valids[MDOC_MAX] = {
-	{ NULL, NULL, NULL }, /* \" */
-	{ NULL, NULL, NULL }, /* Dd */ /* TODO */
-	{ NULL, NULL, NULL }, /* Dt */ /* TODO */
-	{ NULL, NULL, NULL }, /* Os */ /* TODO */
-	{ NULL, args_Sh, NULL }, /* Sh */
-	{ NULL, NULL, NULL }, /* Ss */ 
-	{ want_eq0, NULL, NULL }, /* Pp */ 
-	{ NULL, args_blocknest, need_head_child }, /* D1 */
-	{ NULL, args_blocknest, need_head_child }, /* Dl */
-	{ NULL, args_blocknest, NULL }, /* Bd */
-	{ NULL, NULL, no_head_child }, /* Ed */
-	{ NULL, NULL, NULL }, /* Bl */
-	{ NULL, NULL, no_head_child }, /* El */
-	{ NULL, NULL, NULL }, /* It */
-	{ need_ge1, NULL, NULL }, /* Ad */ 
-	{ NULL, NULL, NULL }, /* An */  /* FIXME: no args & argv. */
-	{ NULL, NULL, NULL }, /* Ar */
-	{ need_ge1, NULL, NULL }, /* Cd */
-	{ NULL, NULL, NULL }, /* Cm */
-	{ need_ge1, NULL, NULL }, /* Dv */ 
-	{ need_ge1, NULL, NULL }, /* Er */ 
-	{ need_ge1, NULL, NULL }, /* Ev */ 
-	{ NULL, NULL, NULL }, /* Ex */
-	{ need_ge1, NULL, NULL }, /* Fa */ 
-	{ NULL, NULL, NULL }, /* Fd */ 
-	{ NULL, NULL, NULL }, /* Fl */
-	{ need_ge1, NULL, NULL }, /* Fn */ 
-	{ want_ge1, NULL, NULL }, /* Ft */ 
-	{ need_ge1, NULL, NULL }, /* Ic */ 
-	{ need_eq1, NULL, NULL }, /* In */ 
-	{ want_ge1, NULL, NULL }, /* Li */
-	{ want_ge1, NULL, NULL }, /* Nd */ 
-	{ NULL, NULL, NULL }, /* Nm */ 
-	{ NULL, NULL, NULL }, /* Op */
-	{ NULL, NULL, NULL }, /* Ot */
-	{ want_ge1, NULL, NULL }, /* Pa */
-	{ NULL, NULL, NULL }, /* Rv */
-	{ NULL, NULL, NULL }, /* St */
-	{ need_ge1, NULL, NULL }, /* Va */
-	{ need_ge1, NULL, NULL }, /* Vt */ 
-	{ need_le2, args_Xr, NULL }, /* Xr */
-	{ need_ge1, args_ref, NULL }, /* %A */
-	{ need_ge1, args_ref, NULL }, /* %B */
-	{ need_ge1, args_ref, NULL }, /* %D */
-	{ need_ge1, args_ref, NULL }, /* %I */
-	{ need_ge1, args_ref, NULL }, /* %J */
-	{ need_ge1, args_ref, NULL }, /* %N */
-	{ need_ge1, args_ref, NULL }, /* %O */
-	{ need_ge1, args_ref, NULL }, /* %P */
-	{ need_ge1, args_ref, NULL }, /* %R */
-	{ need_ge1, args_ref, NULL }, /* %T */
-	{ need_ge1, args_ref, NULL }, /* %V */
-	{ NULL, NULL, NULL }, /* Ac */
-	{ NULL, NULL, NULL }, /* Ao */
-	{ NULL, NULL, NULL }, /* Aq */
-	{ need_le2, args_At, NULL }, /* At */
-	{ NULL, NULL, NULL }, /* Bc */
-	{ NULL, NULL, NULL }, /* Bf */ 
-	{ NULL, NULL, NULL }, /* Bo */
-	{ NULL, NULL, NULL }, /* Bq */
-	{ assert_le1, NULL, NULL }, /* Bsx */
-	{ assert_le1, NULL, NULL }, /* Bx */
-	{ need_eq1, args_bool, NULL }, /* Db */
-	{ NULL, NULL, NULL }, /* Dc */
-	{ NULL, NULL, NULL }, /* Do */
-	{ NULL, NULL, NULL }, /* Dq */
-	{ NULL, NULL, NULL }, /* Ec */
-	{ NULL, NULL, NULL }, /* Ef */ /* -symbolic, etc. */
-	{ need_ge1, NULL, NULL }, /* Em */ 
-	{ NULL, NULL, NULL }, /* Eo */
-	{ assert_le1, NULL, NULL }, /* Fx */
-	{ want_ge1, NULL, NULL }, /* Ms */
-	{ NULL, NULL, NULL }, /* No */
-	{ NULL, NULL, NULL }, /* Ns */
-	{ assert_le1, NULL, NULL }, /* Nx */
-	{ assert_le1, NULL, NULL }, /* Ox */
-	{ NULL, NULL, NULL }, /* Pc */
-	{ NULL, NULL, NULL }, /* Pf */ /* 2 or more arguments */
-	{ NULL, NULL, NULL }, /* Po */
-	{ NULL, NULL, NULL }, /* Pq */
-	{ NULL, NULL, NULL }, /* Qc */
-	{ NULL, NULL, NULL }, /* Ql */
-	{ NULL, NULL, NULL }, /* Qo */
-	{ NULL, NULL, NULL }, /* Qq */
-	{ NULL, NULL, NULL }, /* Re */
-	{ NULL, NULL, NULL }, /* Rs */
-	{ NULL, NULL, NULL }, /* Sc */
-	{ NULL, NULL, NULL }, /* So */
-	{ NULL, NULL, NULL }, /* Sq */
-	{ need_eq1, args_bool, NULL }, /* Sm */
-	{ need_ge1, NULL, NULL }, /* Sx */
-	{ need_ge1, NULL, NULL }, /* Sy */
-	{ want_ge1, NULL, NULL }, /* Tn */
-	{ assert_eq0, NULL, NULL }, /* Ux */
-	{ NULL, NULL, NULL }, /* Xc */
-	{ NULL, NULL, NULL }, /* Xo */
-	{ NULL, NULL, NULL }, /* Fo */ 
-	{ NULL, NULL, NULL }, /* Fc */ 
-	{ NULL, NULL, NULL }, /* Oo */
-	{ NULL, NULL, NULL }, /* Oc */
-	{ NULL, NULL, NULL }, /* Bk */
-	{ NULL, NULL, NULL }, /* Ek */
-	{ need_eq0, NULL, NULL }, /* Bt */
-	{ need_eq1, NULL, NULL }, /* Hf */
-	{ NULL, NULL, NULL }, /* Fr */
-	{ need_eq0, NULL, NULL }, /* Ud */
+	{ NULL, NULL, NULL, NULL }, /* \" */
+	{ NULL, NULL, NULL, NULL }, /* Dd */ /* TODO */
+	{ NULL, NULL, NULL, NULL }, /* Dt */ /* TODO */
+	{ NULL, NULL, NULL, NULL }, /* Os */ /* TODO */
+	{ want_ge1, args_sh, NULL, NULL }, /* Sh */
+	{ want_ge1, NULL, NULL, NULL }, /* Ss */ 
+	{ want_eq0, NULL, NULL, NULL }, /* Pp */ 
+	{ assert_eq0, NULL, tree_pre_display, tree_post_onlyhead }, /* D1 */
+	{ assert_eq0, NULL, tree_pre_display, tree_post_onlyhead }, /* Dl */
+	{ want_eq0, NULL, tree_pre_display, tree_post_warnemptybody }, /* Bd */
+	{ assert_eq0, NULL, NULL, tree_post_onlybody }, /* Ed */
+	{ want_eq0, NULL, NULL, NULL }, /* Bl */
+	{ assert_eq0, NULL, NULL, tree_post_onlybody }, /* El */
+	{ NULL, NULL, NULL, NULL }, /* It */
+	{ need_ge1, NULL, NULL, NULL }, /* Ad */ 
+	{ NULL, args_an, NULL, NULL }, /* An */
+	{ NULL, NULL, NULL, NULL }, /* Ar */
+	{ need_ge1, NULL, NULL, NULL }, /* Cd */
+	{ NULL, NULL, NULL, NULL }, /* Cm */
+	{ need_ge1, NULL, NULL, NULL }, /* Dv */ 
+	{ need_ge1, NULL, NULL, NULL }, /* Er */ 
+	{ need_ge1, NULL, NULL, NULL }, /* Ev */ 
+	{ NULL, NULL, NULL, NULL }, /* Ex */
+	{ need_ge1, NULL, NULL, NULL }, /* Fa */ 
+	{ NULL, NULL, NULL, NULL }, /* Fd */ 
+	{ NULL, NULL, NULL, NULL }, /* Fl */
+	{ need_ge1, NULL, NULL, NULL }, /* Fn */ 
+	{ want_ge1, NULL, NULL, NULL }, /* Ft */ 
+	{ need_ge1, NULL, NULL, NULL }, /* Ic */ 
+	{ need_eq1, NULL, NULL, NULL }, /* In */ 
+	{ want_ge1, NULL, NULL, NULL }, /* Li */
+	{ want_ge1, NULL, NULL, NULL }, /* Nd */ 
+	{ NULL, NULL, NULL, NULL }, /* Nm */ 
+	{ NULL, NULL, NULL, NULL }, /* Op */
+	{ NULL, NULL, NULL, NULL }, /* Ot */
+	{ want_ge1, NULL, NULL, NULL }, /* Pa */
+	{ NULL, NULL, NULL, NULL }, /* Rv */
+	{ NULL, NULL, NULL, NULL }, /* St */
+	{ need_ge1, NULL, NULL, NULL }, /* Va */
+	{ need_ge1, NULL, NULL, NULL }, /* Vt */ 
+	{ need_le2, args_xr, NULL, NULL }, /* Xr */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %A */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %B */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %D */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %I */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %J */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %N */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %O */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %P */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %R */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %T */
+	{ need_ge1, NULL, tree_pre_ref, NULL }, /* %V */
+	{ NULL, NULL, NULL, NULL }, /* Ac */
+	{ NULL, NULL, NULL, NULL }, /* Ao */
+	{ NULL, NULL, NULL, NULL }, /* Aq */
+	{ need_le2, args_nopunct, NULL, NULL }, /* At */
+	{ NULL, NULL, NULL, NULL }, /* Bc */
+	{ NULL, NULL, NULL, NULL }, /* Bf */ 
+	{ NULL, NULL, NULL, NULL }, /* Bo */
+	{ NULL, NULL, NULL, NULL }, /* Bq */
+	{ assert_le1, NULL, NULL, NULL }, /* Bsx */
+	{ assert_le1, NULL, NULL, NULL }, /* Bx */
+	{ need_eq1, args_bool, NULL, NULL }, /* Db */
+	{ NULL, NULL, NULL, NULL }, /* Dc */
+	{ NULL, NULL, NULL, NULL }, /* Do */
+	{ NULL, NULL, NULL, NULL }, /* Dq */
+	{ NULL, NULL, NULL, NULL }, /* Ec */
+	{ NULL, NULL, NULL, NULL }, /* Ef */ /* -symbolic, etc. */
+	{ need_ge1, NULL, NULL, NULL }, /* Em */ 
+	{ NULL, NULL, NULL, NULL }, /* Eo */
+	{ assert_le1, NULL, NULL, NULL }, /* Fx */
+	{ want_ge1, NULL, NULL, NULL }, /* Ms */
+	{ NULL, NULL, NULL, NULL }, /* No */
+	{ NULL, NULL, NULL, NULL }, /* Ns */
+	{ assert_le1, NULL, NULL, NULL }, /* Nx */
+	{ assert_le1, NULL, NULL, NULL }, /* Ox */
+	{ NULL, NULL, NULL, NULL }, /* Pc */
+	{ NULL, NULL, NULL, NULL }, /* Pf */ /* 2 or more arguments */
+	{ NULL, NULL, NULL, NULL }, /* Po */
+	{ NULL, NULL, NULL, NULL }, /* Pq */
+	{ NULL, NULL, NULL, NULL }, /* Qc */
+	{ NULL, NULL, NULL, NULL }, /* Ql */
+	{ NULL, NULL, NULL, NULL }, /* Qo */
+	{ NULL, NULL, NULL, NULL }, /* Qq */
+	{ NULL, NULL, NULL, NULL }, /* Re */
+	{ NULL, NULL, NULL, NULL }, /* Rs */
+	{ NULL, NULL, NULL, NULL }, /* Sc */
+	{ NULL, NULL, NULL, NULL }, /* So */
+	{ NULL, NULL, NULL, NULL }, /* Sq */
+	{ need_eq1, args_bool, NULL, NULL }, /* Sm */
+	{ need_ge1, NULL, NULL, NULL }, /* Sx */
+	{ need_ge1, NULL, NULL, NULL }, /* Sy */
+	{ want_ge1, NULL, NULL, NULL }, /* Tn */
+	{ assert_eq0, NULL, NULL, NULL }, /* Ux */
+	{ NULL, NULL, NULL, NULL }, /* Xc */
+	{ NULL, NULL, NULL, NULL }, /* Xo */
+	{ NULL, NULL, NULL, NULL }, /* Fo */ 
+	{ NULL, NULL, NULL, NULL }, /* Fc */ 
+	{ NULL, NULL, NULL, NULL }, /* Oo */
+	{ NULL, NULL, NULL, NULL }, /* Oc */
+	{ NULL, NULL, NULL, NULL }, /* Bk */
+	{ NULL, NULL, NULL, NULL }, /* Ek */
+	{ need_eq0, NULL, NULL, NULL }, /* Bt */
+	{ need_eq1, NULL, NULL, NULL }, /* Hf */
+	{ NULL, NULL, NULL, NULL }, /* Fr */
+	{ need_eq0, NULL, NULL, NULL }, /* Ud */
 };
 
 
@@ -248,16 +254,49 @@ need_ge1(struct mdoc *mdoc, int tok, int pos, int sz)
 
 
 static int
-no_head_child(struct mdoc *mdoc, int tok, int pos)
+tree_post_onlybody(struct mdoc *mdoc, int tok, int pos)
 {
+	struct mdoc_node *n;
 
-	/* TODO */
-	return(1);
+	assert(mdoc->last);
+	n = mdoc->last;
+
+	assert(MDOC_BLOCK == n->type);
+	assert(n->child);
+
+	if (MDOC_BODY == n->child->type) {
+		if (n->child->child)
+			return(1);
+		return(mdoc_err(mdoc, tok, pos, ERR_SYNTAX_EMPTYBODY));
+	}
+
+	return(mdoc_err(mdoc, tok, pos, ERR_SYNTAX_CHILDBODY));
 }
 
 
 static int
-need_head_child(struct mdoc *mdoc, int tok, int pos)
+tree_post_warnemptybody(struct mdoc *mdoc, int tok, int pos)
+{
+	struct mdoc_node *n;
+
+	assert(mdoc->last);
+	n = mdoc->last;
+
+	assert(MDOC_BLOCK == n->type);
+	assert(n->child);
+
+	for (n = n->child; n; n = n->next)
+		if (MDOC_BODY == n->type)
+			break;
+
+	if (n && n->child)
+		return(1);
+	return(mdoc_warn(mdoc, tok, pos, WARN_SYNTAX_EMPTYBODY));
+}
+
+
+static int
+tree_post_onlyhead(struct mdoc *mdoc, int tok, int pos)
 {
 	struct mdoc_node *n;
 
@@ -270,16 +309,29 @@ need_head_child(struct mdoc *mdoc, int tok, int pos)
 	n = n->child;
 
 	if (MDOC_HEAD != n->type) 
-		return(mdoc_err(mdoc, tok, pos, ERR_CHILD_HEAD));
+		return(mdoc_err(mdoc, tok, pos, ERR_SYNTAX_CHILDHEAD));
 	if (n->child)
 		return(1);
-	return(mdoc_err(mdoc, tok, pos, ERR_CHILD_HEAD));
+	return(mdoc_err(mdoc, tok, pos, ERR_SYNTAX_EMPTYHEAD));
 }
 
 
 static int
-args_Sh(struct mdoc *mdoc, int tok, int pos, 
-		int sz, const char *args[], 
+args_an(struct mdoc *mdoc, int tok, int pos, 
+		int sz, const char *args[],
+		int argc, const struct mdoc_arg *argv)
+{
+
+	printf("argc=%d, sz=%d\n", argc, sz);
+	if (0 != argc && 0 != sz) 
+		return(mdoc_warn(mdoc, tok, pos, WARN_ARGS_EQ0));
+	return(1);
+}
+
+
+static int
+args_sh(struct mdoc *mdoc, int tok, int pos, 
+		int sz, const char *args[],
 		int argc, const struct mdoc_arg *argv)
 {
 	enum mdoc_sec	 sec;
@@ -297,23 +349,24 @@ args_Sh(struct mdoc *mdoc, int tok, int pos,
 
 static int
 args_bool(struct mdoc *mdoc, int tok, int pos, 
-		int sz, const char *args[], 
+		int sz, const char *args[],
 		int argc, const struct mdoc_arg *argv)
 {
+	int	 	 i;
 
-	assert(1 == sz);
-	if (xstrcmp(args[0], "on"))
-		return(1);	
-	if (xstrcmp(args[0], "off"))
-		return(1);
-	return(mdoc_err(mdoc, tok, pos, ERR_SYNTAX_ARGBAD));
+	for (i = 0; i < sz; i++) {
+		if (xstrcmp(args[i], "on"))
+			continue;
+		if (xstrcmp(args[i], "off"))
+			continue;
+		return(mdoc_err(mdoc, tok, pos, ERR_SYNTAX_ARGBAD));
+	}
+	return(1);
 }
 
 
 static int
-args_ref(struct mdoc *mdoc, int tok, int pos, 
-		int sz, const char *args[], 
-		int argc, const struct mdoc_arg *argv)
+tree_pre_ref(struct mdoc *mdoc, int tok, int pos)
 {
 	struct mdoc_node *n;
 
@@ -331,8 +384,8 @@ args_ref(struct mdoc *mdoc, int tok, int pos,
 
 
 static int
-args_Xr(struct mdoc *mdoc, int tok, int pos, 
-		int sz, const char *args[], 
+args_xr(struct mdoc *mdoc, int tok, int pos, 
+		int sz, const char *args[],
 		int argc, const struct mdoc_arg *argv)
 {
 
@@ -340,7 +393,6 @@ args_Xr(struct mdoc *mdoc, int tok, int pos,
 		return(1);
 	if (0 == sz)
 		return(mdoc_err(mdoc, tok, pos, ERR_ARGS_GE1));
-
 	if (MSEC_DEFAULT == mdoc_atomsec(args[1]))
 		return(mdoc_err(mdoc, tok, pos, ERR_SYNTAX_ARGFORM));
 	return(1);
@@ -348,8 +400,8 @@ args_Xr(struct mdoc *mdoc, int tok, int pos,
 
 
 static int
-args_At(struct mdoc *mdoc, int tok, int pos, 
-		int sz, const char *args[], 
+args_nopunct(struct mdoc *mdoc, int tok, int pos, 
+		int sz, const char *args[],
 		int argc, const struct mdoc_arg *argv)
 {
 	int		 i;
@@ -360,7 +412,6 @@ args_At(struct mdoc *mdoc, int tok, int pos,
 	i = 0;
 	if (ATT_DEFAULT == mdoc_atoatt(args[i]))
 		i++;
-
 	for ( ; i < sz; i++) {
 		if ( ! mdoc_isdelim(args[i]))
 			continue;
@@ -371,19 +422,14 @@ args_At(struct mdoc *mdoc, int tok, int pos,
 
 
 static int
-args_blocknest(struct mdoc *mdoc, int tok, int pos, 
-		int sz, const char *args[], 
-		int argc, const struct mdoc_arg *argv)
+tree_pre_display(struct mdoc *mdoc, int tok, int pos)
 {
 	struct mdoc_node *node;
 
-	/*
-	 * We can't be nested within any other block displays (or really
-	 * any other kind of display, although Bd is the only multi-line
-	 * one that will show up). 
-	 */
 	assert(mdoc->last);
 
+	/* Displays may not be nested in other displays. */
+
 	/* LINTED */
 	for (node = mdoc->last; node; node = node->parent) {
 		if (node->type != MDOC_BLOCK)
@@ -408,11 +454,14 @@ mdoc_valid_pre(struct mdoc *mdoc, int tok, int pos,
 	if (mdoc_valids[tok].sz) 
 		if ( ! (*mdoc_valids[tok].sz)(mdoc, tok, pos, sz))
 			return(0);
-
-	if (NULL == mdoc_valids[tok].args) 
-		return(1);
-	return((*mdoc_valids[tok].args)(mdoc, 
-			tok, pos, sz, args, argc, argv));
+	if (mdoc_valids[tok].args) 
+		if ( ! (*mdoc_valids[tok].args)(mdoc, tok, pos, 
+					sz, args, argc, argv))
+			return(0);
+	if (mdoc_valids[tok].tree_pre) 
+		if ( ! (*mdoc_valids[tok].tree_pre)(mdoc, tok, pos))
+			return(0);
+	return(1);
 }
 
 
@@ -420,7 +469,8 @@ int
 mdoc_valid_post(struct mdoc *mdoc, int tok, int pos)
 {
 
-	if (NULL == mdoc_valids[tok].post)
-		return(1);
-	return((*mdoc_valids[tok].post)(mdoc, tok, pos));
+	if (mdoc_valids[tok].tree_post)
+		return((*mdoc_valids[tok].tree_post)(mdoc, tok, pos));
+	return(1);
 }
+