Implement in-line equations, much needed by Xenocara manuals.

Put the steering into the roff parser rather than into the mdoc
parser such that it works for all macro languages and on both text
and macro lines.
Line breaks and blank characters generated before and after in-line
equations are not perfect yet, but let's do one thing at a time.

1 files changed, 26 insertions, 0 deletions

diff --git a/eqn.c b/eqn.c
index 64f2348d..19bd6910 100644
--- a/eqn.c
+++ b/eqn.c
@@ -588,6 +588,30 @@ eqn_box_makebinary(struct eqn_node *ep,
 }
 
 /*
+ * Parse the "delim" control statement.
+ */
+static void
+eqn_delim(struct eqn_node *ep)
+{
+	const char	*start;
+	size_t		 sz;
+
+	if ((start = eqn_nextrawtok(ep, &sz)) == NULL)
+		mandoc_msg(MANDOCERR_REQ_EMPTY, ep->parse,
+		    ep->eqn.ln, ep->eqn.pos, "delim");
+	else if (strncmp(start, "off", 3) == 0)
+		ep->delim = 0;
+	else if (strncmp(start, "on", 2) == 0) {
+		if (ep->odelim && ep->cdelim)
+			ep->delim = 1;
+	} else if (start[1] != '\0') {
+		ep->odelim = start[0];
+		ep->cdelim = start[1];
+		ep->delim = 1;
+	}
+}
+
+/*
  * Undefine a previously-defined string.
  */
 static int
@@ -698,6 +722,8 @@ this_tok:
 			EQN_MSG(MANDOCERR_EQNEOF, ep);
 		break;
 	case (EQN_TOK_DELIM):
+		eqn_delim(ep);
+		break;
 	case (EQN_TOK_GFONT):
 		if (eqn_nextrawtok(ep, NULL) == NULL)
 			mandoc_msg(MANDOCERR_REQ_EMPTY, ep->parse,