Separated Turing machine implementation into components

* i.e. separate namespaces and headers for _Tape_ and _State_ functions
* `void` is now used as the `BLANK` field value

1 files changed, 46 insertions, 0 deletions

diff --git a/example/turing/src/tape.h b/example/turing/src/tape.h
new file mode 100644
index 0000000..39814d8
--- /dev/null
+++ b/example/turing/src/tape.h
@@ -0,0 +1,46 @@
+#ifndef TYPEASVALUE_EXAMPLE_TURING_SRC_TAPE_H_
+#define TYPEASVALUE_EXAMPLE_TURING_SRC_TAPE_H_
+
+#include "type.h"
+#include "list/list.h"
+#include "list/operation/replace_nth.h"
+#include "conditional/if.h"
+
+namespace machine {
+
+namespace tape {
+
+// (define (readSymbol position tape)
+//   (if (= (length tape) position)
+//       '()
+//       (nth position tape)))
+template <
+	typename Position,
+	typename Tape
+>
+using readSymbol = tav::If<
+	tav::IsEqualValue<tav::Length<Tape>, Position>,
+	void,
+	tav::Nth<Position, Tape>
+>;
+
+// (define (writeSymbol position symbol tape)
+//   (if (= (length tape) position)
+//       (append tape (list symbol))
+//       (replace-nth position symbol tape)))
+template <
+	typename Position,
+	typename Symbol,
+	typename Tape
+>
+using writeSymbol = tav::If<
+	tav::IsEqualValue<tav::Length<Tape>, Position>,
+	tav::Append<Tape, tav::List<Symbol>>,
+	tav::ReplaceNth<Position, Symbol, Tape>
+>;
+
+}
+
+}
+
+#endif // TYPEASVALUE_EXAMPLE_TURING_SRC_TAPE_H_