added a double lambda test case

lib/read.c

@@ -1335,13 +1335,12 @@ static int feed_process_token (hcl_t* hcl)
 		case HCL_TOK_LPAREN: /* ( */
 #if defined(HCL_LANG_AUTO_FORGE_XLIST_ALWAYS)
 			/* with this feature on, you must not enclose an expression with ()
-			 * at the top-level or a the block level. If you do, it is interpreted as
-			 * double exuection, meaning the return value of the expression is
-			 * called again.
-			 *
-			 * (+ 10 20) as a leading expression is like ((+ 10 20)).
+			 * at the beginning of the top-level or at the beginning of a the block level.
+			 * If you do enclose an expression with an outer () there, it is interpreted as
+			 * double calls, meaning the return value of the expression is called again.
+			 * for example, '(+ 10 20)' as a leading expression is like '((+ 10 20))'.
 			 * -------------------------------------------------------------
-			 * However, it can be a bit confusing:
+			 * It is useful but a bit confusing:
 			 *   defun x(a) { return (fun(b) { return (+ a b) }) }
 			 *   printf "%d\n" ((x 10) 20)   ## excplicit outer () is required here
 			 *   (x 10) 30  ## explicit outer () must not be used here

t/fun-01.hcl

@@ -18,7 +18,16 @@ defun mkfun(t) {
 	return (fun(c) {
 		return (+ t c);
 	});
-};
+}
+
+defun mkfund(t) {
+	return {fun(c) {
+		return (fun(d) {
+			##return (d + c t) ## this causes assertion failure.
+			return (d + c t)
+		})
+	}}
+}
 
 f := (mkfun 20);
 set k (f 50);
@@ -38,7 +47,9 @@ if (k = 50) {
 };
 
 k := {
-	(mkfun 20) 30
+	## the return value of this expression is ignored
+	(mkfun 20) 30  ## having comment here cause an issue...
+	## the return value of this expression is the return value of the block expression
 	(mkfun 20) 40
 }
 if (k = 60) {
@@ -47,6 +58,12 @@ if (k = 60) {
 	printf "ERROR - %d\n" k
 };
 
+k := (((mkfund 10) 40) 30)
+if (k = 80) {
+	printf "OK - %d\n" k
+} else {
+	printf "ERROR - %d\n" k
+};
 ## --------------------------------------
 
 defclass A | a b c | {

t/run.sh

@@ -1,5 +1,6 @@
 #!/bin/sh
 ## use a subshell to execute the actual program in case the
 ## program crashes or exits without an error message.
+echo RUN "[$@]"
 ($@ 2>&1 || echo "ERROR: exited with $?") | grep -E '^ERROR:' && exit 1
 exit 0