cxrefbas and renumbas: round fractional line numbers like BASIC does.

1 files changed, 12 insertions, 0 deletions

diff --git a/linetab.c b/linetab.c
index 0351f59..59a96e3 100644
--- a/linetab.c
+++ b/linetab.c
@@ -93,6 +93,8 @@ void computed_msg(unsigned short lineno) {
 
 CALLBACK(got_var) {
 	switch(last_cmd) {
+		/* any use of a variable in the arguments to these means
+		   we can't renumber that argument. */
 		case CMD_GOTO:
 		case CMD_GO_TO:
 		case CMD_GOSUB:
@@ -102,6 +104,7 @@ CALLBACK(got_var) {
 			computed_msg(lineno);
 			break;
 		case CMD_ON:
+			/* vars are OK in ON, before the GOTO or GOSUB */
 			if(on_op) computed_msg(lineno);
 			break;
 		default:
@@ -119,9 +122,14 @@ CALLBACK(got_exp) {
 	}
 
 	if(tok != OP_NUMCONST) return;
+
+	/* beware: standalone only means nothing *follows* the constant
+	   in the same expression. still have to check last_tok to see
+	   what came before. */
 	standalone = is_standalone_num(pos);
 
 	switch(last_cmd) {
+		/* these take a single argument */
 		case CMD_GOTO:
 		case CMD_GO_TO:
 		case CMD_GOSUB:
@@ -134,11 +142,14 @@ CALLBACK(got_exp) {
 			}
 			break;
 		case CMD_IF:
+			/* this only applies to bare line numbers, like IF A THEN 1000,
+			   not IF A THEN GOTO 1000 (or anything else after THEN). */
 			if(last_tok == OP_THEN) {
 				add_lineref(lineno, pos + 1);
 			}
 			break;
 		case CMD_ON: {
+				/* takes arbitrary number of arguments */
 				switch(last_tok) {
 					case OP_GOTO:
 					case OP_GOSUB:
@@ -154,6 +165,7 @@ CALLBACK(got_exp) {
 			}
 			break;
 		case CMD_LIST: {
+				/* takes one or two arguments */
 				switch(last_tok) {
 					case CMD_LIST:
 					case OP_COMMA: