1 files changed, 66 insertions, 0 deletions
diff --git a/include/mm/view.hpp b/include/mm/view.hpp
new file mode 100644
index 0000000..910c16a
--- /dev/null
+++ b/include/mm/view.hpp
@@ -0,0 +1,66 @@
+#pragma once
+
+#include <mmmatrix.hpp>
+
+
+namespace mm::alg {
+
+	template <
+		template<typename, std::size_t, std::size_t> typename Matrix,
+		typename T, std::size_t Rows, std::size_t Cols
+	>
+	struct visitor
+	{
+		using type = T;
+
+		// copy constructible
+		visitor(const visitor& other) = default;
+
+		T& operator()(const Matrix<T, Rows, Cols>& m, index row, index col) {
+			return m.at(row, col);
+		}
+
+		const T& operator()(const Matrix<T, Rows, Cols>& m, index row, index col) {
+			return operator()(m, row, col);
+		}
+	};
+
+	template <
+		template<typename, std::size_t, std::size_t> typename Matrix,
+		typename T, std::size_t Rows, std::size_t Cols
+	>
+	struct transpose : public visitor<Matrix, T, Rows, Cols>
+	{
+		T& operator()(const Matrix<T, Rows, Cols> m, index row, index col) {
+			// assert(col < Rows)
+			// assert(row < Cols)
+			return m.at(col, row);
+		}
+	};
+}
+
+namespace mm {
+	template <
+		template<typename, std::size_t, std::size_t> typename Matrix,
+		typename T, std::size_t Rows, std::size_t Cols
+	>
+	struct view
+	{
+		Matrix<T, Rows, Cols>& m;
+		// std::stack<std::unique_ptr<alg::visitor>> visitors;
+		std::unique_ptr<alg::visitor> visitor;
+
+		T& at(index row, index col) {
+			return visitor(m, row, col);
+		}
+
+		view& operator|=(const alg::visitor& other) {
+			// visitors.push(std::move(std::make_unique<alg::visitor>(other)));
+			visitor = std::make_unique<alg::visistor>(other);
+		}
+	};
+
+	view operator|(const view& left, const alg::visitor& right) {
+		return left |= right;
+	}
+}