old_contents: export { Base };
  
  /**
   * Count how many operations use a tensor behind this counter.
   *
   * @member {any} tensorId
   *   This tensor's identifier.
   *
   * @member {Base} input0
   *   The first TensorOpCounter which is just before this TensorOpCounter.
   *
   * @member {Base} input1
   *   The second TensorOpCounter which is just before this TensorOpCounter.
   *
   * @member {number} behindOperationCount
   *   This tensor is used by how many operations which is behind this operation. If zero, the tensor is not used by other operation.
   *
   * @member {Base[]} nextOperationArray
   *   The operations behind this operation.
   *
   *
   *
   */
  class Base {
  
    constructor( tensorId, input0, input1 ) {
      this.tensorId = tensorId;
      this.input0 = input0;
      this.input1 = input1;
      this.behindOperationCount = 0;
      this.nextOperationArray = [];
  
      if ( input0 )
        input0.nextOperationArray.push( this );
  
      if ( input1 )
        input1.nextOperationArray.push( this );
    }
  
  }
  
new_contents: export { Base };
  
  /**
   * Count how many operations use a tensor behind this counter.
   *
   * @member {any} tensorId
   *   This tensor's identifier.
   *
   * @member {object} operationObject
   *   The object which implements the operation. It should have a pfnOperation() method.
   *
   * @member {Base} input0
   *   The first TensorOpCounter which is just before this TensorOpCounter.
   *
   * @member {Base} input1
   *   The second TensorOpCounter which is just before this TensorOpCounter.
   *
   * @member {number} behindOperationCount
   *   This tensor is used by how many operations which is behind this operation. If zero, the tensor is not used by other operation.
   *
   * @member {Base[]} nextOperationArray
   *   The operations behind this operation.
   *
   *
   *
   */
  class Base {
  
    constructor( tensorId, operationObject, input0, input1 ) {
      this.tensorId = tensorId;
      this.operationObject = operationObject;
      this.input0 = input0;
      this.input1 = input1;
      this.behindOperationCount = 0;
      this.nextOperationArray = [];
  
      if ( input0 )
        input0.nextOperationArray.push( this );
  
      if ( input1 )
        input1.nextOperationArray.push( this );
    }
  
  }
  
subject: Update TensorOpCounter.js