#ifndef MATRIX_PROXY_H
#define MATRIX_PROXY_H

#include "range.h"
#include "matrix_expression.h"

/*****************************************************
 * matrix_proxy class
 ****************************************************/
class matrix_proxy : public matrix_expression {
 private:
  matrix_expression& _M;  // reference to the underlying source (which may be matrix or proxy)
  const range _rows;      // copy of range describe extent of rows
  const range _cols;      // copy of range describing extent of columns

 public:

  // use inherited assignment operator (rather than default)
  using matrix_expression::operator=;
  matrix_proxy& operator=(const matrix_proxy& other);

  // constructor
  matrix_proxy(matrix_expression& src, const range& rows, const range& ccols);

  int numRows() const;

  int numColumns() const;

  // read-only version of indexing operator
  double operator()(int r, int c) const;

  // write-access version of indexing operator
  double& operator()(int r, int c);

};


#endif