fix looping from issue 2467

src/toplevel.pl

@@ -168,7 +168,9 @@ repl :-
 %% Enable op declarations with lists of operands, i.e.,
 %% :- op(900, fy, [$,@]).
 
-user:term_expansion((:- op(Pred, Spec, [Op | OtherOps])), OpResults) :-
+user:term_expansion((:- op(Pred, Spec, Ops)), OpResults) :- 
+    ground(Ops), 
+    Ops = [Op | OtherOps],
     expand_op_list([Op | OtherOps], Pred, Spec, OpResults).
 
 expand_op_list([], _, _, []).

tests-pl/invalid_decl_issue2467.pl

@@ -0,0 +1 @@
+:- D.

tests/scryer/cli/src_tests/directive_errors.md

@@ -59,13 +59,14 @@ $ scryer-prolog -f --no-add-history tests-pl/invalid_decl10.pl -g halt
 
 ```
 
-The following test doesn't appear to terminate so its moved to a block quote for now
+FIXME I belive the following test should result in a `error(instantiation_error,load/1)` error instead of the current error.
 
-> ```trycmd
-> $ scryer-prolog -f --no-add-history tests-pl/invalid_decl11.pl -g halt
-> % Warning: singleton variables Var at line 0 of invalid_decl11.pl
->    error(instantiation_error,load/1).
-> ```
+```trycmd
+$ scryer-prolog -f --no-add-history tests-pl/invalid_decl11.pl -g halt
+% Warning: singleton variables Var at line 0 of invalid_decl11.pl
+   error(type_error(list,todo_insert_invalid_term_here),load/1).
+
+```
 
 ```trycmd
 $ scryer-prolog -f --no-add-history tests-pl/invalid_decl12.pl -g halt
@@ -96,3 +97,11 @@ $ scryer-prolog -f --no-add-history tests-pl/invalid_decl16.pl -g halt
    error(permission_error(modify,operator,','),load/1).
 
 ```
+
+
+```trycmd
+$ scryer-prolog -f --no-add-history tests-pl/invalid_decl_issue2467.pl -g halt
+% Warning: singleton variables D at line 0 of invalid_decl_issue2467.pl
+   error(instantiation_error,load/1).
+
+```