Make errors more like dyalog:

* Use the same error numbers
* Rename ⎕THROW to ⎕SIGNAL
* Implement ⎕EN to inspect the last error code
* Implement ⎕EM to get a message from an error code

1 files changed, 8 insertions, 4 deletions

diff --git a/main.c b/main.c
index 60beed2..d67d742 100644
--- a/main.c
+++ b/main.c
@@ -33,10 +33,14 @@ threadmain(int argc, char *argv[])
 restart:
 	if(setjmp(eg->jmp)){
 		ThreadData *td = getthreaddata();
-		if(td->lasterrormsg)
-			print("%S: %S\n", errorstrs[td->lasterror], td->lasterrormsg);
-		else
-			print("%S\n", errorstrs[td->lasterror]);
+		Rune *msg = errorstr(td->lasterror);
+		if(td->lasterrormsg){
+			if(runestrlen(msg) == 0)
+				print("%S\n", td->lasterrormsg);
+			else
+				print("%S: %S\n", errorstr(td->lasterror), td->lasterrormsg);
+		}else
+			print("%S\n", errorstr(td->lasterror));
 		while(getcurrentdfn())
 			popdfnframe();
 		goto restart;