disambiguate $((…)) vs. $((…)…) in “typeset -f” output

check.t

@@ -1,4 +1,4 @@
-# $MirOS: src/bin/mksh/check.t,v 1.773 2017/04/08 01:07:12 tg Exp $
+# $MirOS: src/bin/mksh/check.t,v 1.774 2017/04/11 12:34:02 tg Exp $
 # -*- mode: sh -*-
 #-
 # Copyright © 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,

tree.c

@@ -23,7 +23,7 @@
 
 #include "sh.h"
 
-__RCSID("$MirOS: src/bin/mksh/tree.c,v 1.87 2017/04/06 01:59:58 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/tree.c,v 1.88 2017/04/11 12:34:04 tg Exp $");
 
 #define INDENT	8
 
@@ -365,6 +365,8 @@ wdvarput(struct shf *shf, const char *wp, int quotelevel, int opmode)
 		case COMSUB:
 			shf_puts("$(", shf);
 			cs = ")";
+			if (*wp == '(' /*)*/)
+				shf_putc(' ', shf);
  pSUB:
 			while ((c = *wp++) != 0)
 				shf_putc(c, shf);