diff --git a/interpreter/src/ir.rs b/interpreter/src/ir.rs
index 34df616..3ab88bd 100644
--- a/interpreter/src/ir.rs
+++ b/interpreter/src/ir.rs
@@ -320,7 +320,6 @@ impl Display for Instruction {
             | OpCode::Negation
             | OpCode::ToInt
             | OpCode::Negative
-            | OpCode::Concat
             | OpCode::Copy) => {
                 let (dest, data) = unsafe { &self.args.unary_local };
                 write!(f, "{dest} <- {op} {data}")
@@ -340,6 +339,7 @@ impl Display for Instruction {
             | OpCode::Multiply
             | OpCode::Divide
             | OpCode::Raise
+            | OpCode::Concat
             | OpCode::Modulo) => {
                 let (dest, lhs, rhs) = unsafe { &self.args.binary_local };
                 write!(f, "{dest} <- {op} {lhs}, {rhs}")
diff --git a/interpreter/src/vm.rs b/interpreter/src/vm.rs
index 818ccca..ce576f4 100644
--- a/interpreter/src/vm.rs
+++ b/interpreter/src/vm.rs
@@ -117,7 +117,7 @@ impl Interpreter<'_> {
                     let src = self.registers.get(src);
                     let val = match ix.opcode {
                         OpCode::Record => todo!(),
-                        OpCode::Negation => Value::Float(!src.to_bool() as usize as f64),
+                        OpCode::Negation => Value::b2f(!src.to_bool()),
                         OpCode::ToInt => Value::Float(src.to_num()),
                         OpCode::Negative => Value::Float(-src.to_num()),
                         _ => unreachable!(),