diff --git a/src/main/wacc/ast.scala b/src/main/wacc/ast.scala
index 3093fcf..16d983c 100644
--- a/src/main/wacc/ast.scala
+++ b/src/main/wacc/ast.scala
@@ -43,9 +43,6 @@ object ast {
       with LValue
   object ArrayElem extends ParserBridge2[String, List[Expr], ArrayElem]
 
-  case class UnaryOper(op: UnaryOperator, expr: Expr6) extends Expr6
-  object UnaryOper extends ParserBridge2[UnaryOperator, Expr6, UnaryOper]
-
   // R values
   sealed trait RValue
 
@@ -58,24 +55,28 @@ object ast {
   case class Call(name: String, args: List[Expr]) extends Expr6 with RValue
   object Call extends ParserBridge2[String, List[Expr], Call]
 
-  // Operators
-  sealed trait UnaryOperator
-  case object Negate extends UnaryOperator with ParserBridge0[Negate.type]
-  case object Not extends UnaryOperator with ParserBridge0[Not.type]
-  case object Len extends UnaryOperator with ParserBridge0[Len.type]
-  case object Ord extends UnaryOperator with ParserBridge0[Ord.type]
-  case object Chr extends UnaryOperator with ParserBridge0[Chr.type]
+  // Unary operators
+  case class Negate(x: Expr6) extends Expr6
+  object Negate extends ParserBridge1[Expr6, Negate]
+  case class Not(x: Expr6) extends Expr6
+  object Not extends ParserBridge1[Expr6, Not]
+  case class Len(x: Expr6) extends Expr6
+  object Len extends ParserBridge1[Expr6, Len]
+  case class Ord(x: Expr6) extends Expr6
+  object Ord extends ParserBridge1[Expr6, Ord]
+  case class Chr(x: Expr6) extends Expr6
+  object Chr extends ParserBridge1[Expr6, Chr]
 
-  sealed trait BinaryOperator
-  case class Add(x: Expr5, y: Expr6) extends Expr5
+  // Binary operators
+  case class Add(x: Expr5, y: Expr6) extends Expr4
   object Add extends ParserBridge2[Expr5, Expr6, Add]
-  case class Sub(x: Expr5, y: Expr6) extends Expr5
+  case class Sub(x: Expr5, y: Expr6) extends Expr4
   object Sub extends ParserBridge2[Expr5, Expr6, Sub]
-  case class Mul(x: Expr6, y: Expr6) extends Expr6
+  case class Mul(x: Expr6, y: Expr6) extends Expr5
   object Mul extends ParserBridge2[Expr6, Expr6, Mul]
-  case class Div(x: Expr6, y: Expr6) extends Expr6
+  case class Div(x: Expr6, y: Expr6) extends Expr5
   object Div extends ParserBridge2[Expr6, Expr6, Div]
-  case class Mod(x: Expr6, y: Expr6) extends Expr6
+  case class Mod(x: Expr6, y: Expr6) extends Expr5
   object Mod extends ParserBridge2[Expr6, Expr6, Mod]
   case class Greater(x: Expr4, y: Expr4) extends Expr3
   object Greater extends ParserBridge2[Expr4, Expr4, Greater]
@@ -85,13 +86,13 @@ object ast {
   object Less extends ParserBridge2[Expr4, Expr4, Less]
   case class LessEq(x: Expr4, y: Expr4) extends Expr3
   object LessEq extends ParserBridge2[Expr4, Expr4, LessEq]
-  case class Eq(x: Expr4, y: Expr4) extends Expr3
-  object Eq extends ParserBridge2[Expr4, Expr4, Eq]
-  case class Neq(x: Expr4, y: Expr4) extends Expr3
-  object Neq extends ParserBridge2[Expr4, Expr4, Neq]
-  case class And(x: Expr2, y: Expr2) extends Expr2
+  case class Eq(x: Expr3, y: Expr3) extends Expr2
+  object Eq extends ParserBridge2[Expr3, Expr3, Eq]
+  case class Neq(x: Expr3, y: Expr3) extends Expr2
+  object Neq extends ParserBridge2[Expr3, Expr3, Neq]
+  case class And(x: Expr2, y: Expr2) extends Expr1
   object And extends ParserBridge2[Expr2, Expr2, And]
-  case class Or(x: Expr1, y: Expr1) extends Expr1
+  case class Or(x: Expr1, y: Expr1) extends Expr
   object Or extends ParserBridge2[Expr1, Expr1, Or]
 
   // Statements