Add under ⍢ and obverse ⍫

Teach inverse() that the inverse of f⍫g is g⍫f


1 files changed, 9 insertions, 0 deletions

diff --git a/inverse.c b/inverse.c
index b37664b..c20e78d 100644
--- a/inverse.c
+++ b/inverse.c
@@ -7,6 +7,15 @@
 Function
 inverse(Function f)
 {
+	/* TODO figure out a good way to structure this code */
+	if(f.type == FunctypeOp && f.operator.type == OperatortypePrim && f.operator.code == 9 && f.operator.dyadic){
+		/* obverse */
+		Function newf = f;
+		newf.operator.left = f.operator.right;
+		newf.operator.right = f.operator.left;
+		return newf;
+	}
+
 	Rune *msg = runesmprint("No inverse defined for %S", ppfunction(f));
 	throwerror(msg, EDomain);
 	return f;