some compiler enhancements

README.md

@@ -17,6 +17,7 @@ A HCL program is composed of expressions.
 - do
 - elif
 - else
+- fun
 - if
 - lambda
 - or
@@ -30,7 +31,7 @@ A HCL program is composed of expressions.
 ```
 do;
 do 10;
-do { | k | set k 20; printf "k=%d\n" k };
+do { | k | set k 20; printf "k=%d\n" k; };
 ```
 
 ## Literals

lib/comp.c

@@ -1822,7 +1822,9 @@ static int compile_break (hcl_t* hcl, hcl_cnode_t* src)
 		}
 	}
 
-	hcl_setsynerrbfmt (hcl, HCL_SYNERR_BREAK, HCL_CNODE_GET_LOC(src), HCL_NULL, "%.*js outside loop", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+	hcl_setsynerrbfmt (
+		hcl, HCL_SYNERR_BREAK, HCL_CNODE_GET_LOC(src), HCL_NULL,
+		"%.*js outside loop", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 	return -1;
 
 inside_loop:
@@ -1860,7 +1862,9 @@ inside_loop:
 
 	/* this part must no be reached. if a loop control block is found,
 	 * there must exist a COP_POST_UNTIL_BODY or COP_POST_WHILE_BODY frame */
-	hcl_setsynerrbfmt (hcl, HCL_SYNERR_INTERN, HCL_CNODE_GET_LOC(src), HCL_NULL, "internal error in compiling %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+	hcl_setsynerrbfmt (
+		hcl, HCL_SYNERR_INTERN, HCL_CNODE_GET_LOC(src), HCL_NULL,
+		"internal error in compiling %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 	return -1;
 }
 

lib/read.c

@@ -1251,7 +1251,7 @@ static int feed_process_token (hcl_t* hcl)
 			}
 
 			concode = LIST_FLAG_GET_CONCODE(rstl->flagv);
-			if (concode != HCL_CONCODE_XLIST)  /* TODO: handle MLIST as weel if the other part is implemented */
+			if (concode != HCL_CONCODE_XLIST)  /* TODO: handle MLIST as well if the other part is implemented */
 			{
 				hcl_setsynerr (hcl, HCL_SYNERR_UNBALPBB, TOKEN_LOC(hcl), HCL_NULL);
 				goto oops;
@@ -1270,6 +1270,7 @@ static int feed_process_token (hcl_t* hcl)
 		{
 			int oldflagv;
 			int concode;
+			hcl_rstl_t* rstl;
 
 			if (frd->level <= 0)
 			{
@@ -1277,6 +1278,17 @@ static int feed_process_token (hcl_t* hcl)
 				goto oops;
 			}
 
+			if (TOKEN_TYPE(hcl) == HCL_TOK_RBRACE)
+			{
+				rstl = hcl->c->r.st; /* check the parent, not the current */
+				if (rstl && (rstl->flagv & AUTO_FORGED))
+				{
+					/* the auto-forged list has not been terminated. it must be terminated closed first */
+					hcl_setsynerrbfmt (hcl, HCL_SYNERR_SEMICOLON, TOKEN_LOC(hcl), TOKEN_NAME(hcl), "semicolon expected");
+					goto oops;
+				}
+			}
+
 			concode = LIST_FLAG_GET_CONCODE(frd->flagv);
 			if (concode == HCL_CONCODE_XLIST && (frd->flagv & AUTO_FORGED))
 			{

t/do-02.err

@@ -0,0 +1,8 @@
+## if `do` is not enclosed in `( )`, it supports only the limited number of expressions.
+
+do ; ## this is ok
+
+do 1; ## this is ok
+
+do { set k 10; printf "k=%d\n" k; } ##ERROR: syntax error - more than one expression after do
+   { set k 20; printf "k=%d\n" k; }; 

t/feed-01.err

@@ -0,0 +1,6 @@
+## the left brace opens a list explicitly and doesn't auto-forge a container list.
+## so the semicolon after it is a redundant one. `do {};` would work because the semicolon
+## terminates the auto-forged list of `do` and `{}`.
+{
+	printf "hello, world\n";
+}; ##ERROR: syntax error - unexpected semicolon

t/var-03.err

@@ -0,0 +1,3 @@
+defclass A | a | {
+	| j | ##ERROR: syntax error - variable declaration disallowed in class init scope
+};