formatStmt (Assign modOp lval expr _) =
  formatLval lval <+> formatModOp modOp <+> formatExpr expr
formatStmt (Assign modOp lval expr _) =
  formatLval lval <+> formatModOp modOp <+> formatExpr expr
formatStmt (Assign modOp lval expr _) =
  formatLval lval <+> formatModOp modOp <+> formatExpr expr