No goal_expansion of head, re issue #901

infradig · infradig · commit bc296adb70ea · 2025-10-24T12:01:30.000+10:00
diff --git a/src/parser.c b/src/parser.c
@@ -2273,7 +2273,9 @@ static cell *term_to_body_conversion(parser *p, cell *c)
 				if ((c->val_off != g_neck_s))
 					lhs = goal_expansion(p, lhs);
 
-				lhs = term_to_body_conversion(p, lhs);
+				if (!is_head)
+					lhs = term_to_body_conversion(p, lhs);
+
 				lhs->arity -= extra;
 			}
 

Original file line number	Diff line number	Diff line change
`@@ -2273,7 +2273,9 @@ static cell term_to_body_conversion(parser p, cell *c)`
`2273`	`2273`	`if ((c->val_off != g_neck_s))`
`2274`	`2274`	`lhs = goal_expansion(p, lhs);`
`2275`	`2275`
`2276`		`- lhs = term_to_body_conversion(p, lhs);`
	`2276`	`+ if (!is_head)`
	`2277`	`+ lhs = term_to_body_conversion(p, lhs);`
	`2278`	`+`
`2277`	`2279`	`lhs->arity -= extra;`
`2278`	`2280`	`}`
`2279`	`2281`