message: Add public operator property into BinaryOperand,
diff: @@ -53,6 +53,9 @@ export class BinaryOperand extends Operand {
  public get conjunction(): string {
  return this.isConjunction ? this.operatorName : "";
  }
  + public get operator(): string {
  + return this.operatorName;
  + }
  public get leftOperand() {
  return this.left;
  }
  