started working on parsing labels

moo/kernel/test-003.moo

@@ -91,6 +91,8 @@ class MyObject(Object)
 			| tb |
 			tb := tc at: idx.
 			System log(System.Log.INFO, idx asString, (if (tb value) { " PASS" } else { " FAIL" }), "\n").
+/*a:
+b: c:*/
 		].
 
 Exception signal: 'experiment with exception signalling'.

moo/lib/comp.c

@@ -984,7 +984,6 @@ static MOO_INLINE int is_token_keyword (moo_t* moo, voca_id_t id)
 	return TOKEN_TYPE(moo) == MOO_IOTOK_KEYWORD && does_token_name_match(moo, id);
 }
 
-
 static MOO_INLINE int add_token_str (moo_t* moo, const moo_ooch_t* ptr, moo_oow_t len)
 {
 	moo_oocs_t tmp;
@@ -4819,7 +4818,7 @@ static int compile_block_expression (moo_t* moo)
 	moo_cunit_class_t* cc = (moo_cunit_class_t*)moo->c->cunit;
 	moo_oow_t jump_inst_pos;
 	moo_oow_t saved_tmpr_count, saved_tmprs_len;
-	moo_oow_t block_arg_count, block_tmpr_count;
+	moo_oow_t block_arg_count, block_tmpr_count, code_start;
 	moo_ioloc_t block_loc, colon_loc, tmpr_loc;
 
 	/*
@@ -4931,6 +4930,7 @@ static int compile_block_expression (moo_t* moo)
 	if (emit_single_param_instruction(moo, BCODE_JUMP_FORWARD_0, MAX_CODE_JUMP, &block_loc) <= -1) return -1;
 
 	/* compile statements inside a block */
+#if 0
 	if (TOKEN_TYPE(moo) == MOO_IOTOK_RBRACK)
 	{
 		/* the block is empty */
@@ -4938,9 +4938,25 @@ static int compile_block_expression (moo_t* moo)
 	}
 	else 
 	{
+		int empty = 1, n;
+
 		while (TOKEN_TYPE(moo) != MOO_IOTOK_EOF)
 		{
-			if (compile_block_statement(moo) <= -1) return -1;
+			n = compile_block_statement(moo);
+			if (n <= -1) return -1;
+			if (n == 8888)
+			{
+				/* compile_block_statement() processed non-statement item like a jump label. */
+				if (TOKEN_TYPE(moo) == MOO_IOTOK_RBRACK) 
+				{
+					if (empty && emit_byte_instruction(moo, BCODE_PUSH_NIL, TOKEN_LOC(moo)) <= -1) return -1;
+					break;
+				}
+			}
+			else
+			{
+				/* a proper statement has been processed in compile_block_statemnt */
+				empty = 0;
 
 				if (TOKEN_TYPE(moo) == MOO_IOTOK_RBRACK) break;
 				else if (TOKEN_TYPE(moo) == MOO_IOTOK_PERIOD)
@@ -4957,6 +4973,48 @@ static int compile_block_expression (moo_t* moo)
 				}
 			}
 		}
+	}
+#else
+	code_start = cc->mth.code.len;
+	if (TOKEN_TYPE(moo) != MOO_IOTOK_RBRACK)
+	{
+		while (TOKEN_TYPE(moo) != MOO_IOTOK_EOF)
+		{
+			int n;
+
+			n = compile_block_statement(moo);
+			if (n <= -1) return -1;
+			if (n == 8888)
+			{
+				/* compile_block_statement() processed non-statement item like a jump label. */
+				if (TOKEN_TYPE(moo) == MOO_IOTOK_RBRACK) break;
+			}
+			else
+			{
+				/* a proper statement has been processed in compile_block_statemnt */
+				if (TOKEN_TYPE(moo) == MOO_IOTOK_RBRACK) break;
+				else if (TOKEN_TYPE(moo) == MOO_IOTOK_PERIOD)
+				{
+					moo_ioloc_t period_loc = *TOKEN_LOC(moo);
+					GET_TOKEN (moo);
+					if (TOKEN_TYPE(moo) == MOO_IOTOK_RBRACK) break;
+					if (emit_byte_instruction(moo, BCODE_POP_STACKTOP, &period_loc) <= -1) return -1;
+				}
+				else
+				{
+					moo_setsynerr (moo, MOO_SYNERR_RBRACK, TOKEN_LOC(moo), TOKEN_NAME(moo));
+					return -1;
+				}
+			}
+		}
+	}
+
+	if (cc->mth.code.len == code_start)
+	{
+		/* the block is empty */
+		if (emit_byte_instruction(moo, BCODE_PUSH_NIL, TOKEN_LOC(moo)) <= -1) return -1;
+	}
+#endif
 
 	if (emit_byte_instruction(moo, BCODE_RETURN_FROM_BLOCK, TOKEN_LOC(moo)) <= -1) return -1;
 
@@ -5996,7 +6054,16 @@ static int compile_braced_block (moo_t* moo)
 	{
 		while (TOKEN_TYPE(moo) != MOO_IOTOK_EOF)
 		{
-			if (compile_block_statement(moo) <= -1) return -1;
+			int n;
+
+			n = compile_block_statement(moo);
+			if (n <= -1) return -1;
+			if (n == 8888)
+			{
+				if (TOKEN_TYPE(moo) == MOO_IOTOK_RBRACE)  break;
+			}
+			else
+			{
 
 				if (TOKEN_TYPE(moo) == MOO_IOTOK_RBRACE) break;
 				else if (TOKEN_TYPE(moo) == MOO_IOTOK_PERIOD)
@@ -6013,6 +6080,7 @@ static int compile_braced_block (moo_t* moo)
 				}
 			}
 		}
+	}
 
 	if (cc->mth.code.len == code_start)
 	{
@@ -6652,6 +6720,14 @@ static int compile_special_statement (moo_t* moo)
 			inject_continue_to_loop(moo, &start_loc): /* in a do-while loop, the position to the conditional is not known yet */
 			emit_backward_jump_instruction(moo, BCODE_JUMP_BACKWARD_0, cc->mth.code.len - cc->mth.loop->startpos, &start_loc);
 	}
+	else if (TOKEN_TYPE(moo) == MOO_IOTOK_KEYWORD)
+	{
+		/* this is a label */
+		/* remember the label location with the block depth */
+MOO_DEBUG2 (moo, "LABEL => %.*js\n", TOKEN_NAME_LEN(moo), TOKEN_NAME_PTR(moo));
+		GET_TOKEN (moo);
+		return 8888; /* indicates that non-statement has been seen and processed.*/
+	}
 
 	return 9999; /* to indicate that no special statement has been seen and processed */
 }
@@ -6744,8 +6820,19 @@ static int compile_method_statements (moo_t* moo)
 	{
 		do
 		{
-			if (compile_method_statement(moo) <= -1) return -1;
+			int n;
 
+			n = compile_method_statement(moo);
+			if (n <= -1) return -1;
+			if (n == 8888)
+			{
+				/* a non-statement such as label has been processed */
+				if (TOKEN_TYPE(moo) == MOO_IOTOK_EOF ||
+				    TOKEN_TYPE(moo) == MOO_IOTOK_RBRACE) break;
+			}
+			else
+			{
+				/* a proper statement has been processed */
 				if (TOKEN_TYPE(moo) == MOO_IOTOK_PERIOD) 
 				{
 					/* period after a statement */
@@ -6764,6 +6851,7 @@ static int compile_method_statements (moo_t* moo)
 					return -1;
 				}
 			}
+		}
 		while (1);
 	}
 

moo/lib/moo-prv.h

@@ -315,7 +315,7 @@ enum moo_iotok_type_t
 	MOO_IOTOK_IDENT,
 	MOO_IOTOK_IDENT_DOTTED,
 	MOO_IOTOK_BINSEL,
-	MOO_IOTOK_KEYWORD,
+	MOO_IOTOK_KEYWORD, /* word ending with : such as basicAt:*/
 	MOO_IOTOK_ASSIGN,  /* := */
 	MOO_IOTOK_COLON,   /* : */
 	MOO_IOTOK_DHASH,   /* ## */