1 files changed, 44 insertions, 0 deletions
diff --git a/cs/step0_repl.cs b/cs/step0_repl.cs
new file mode 100644
index 0000000..665aab6
--- /dev/null
+++ b/cs/step0_repl.cs
@@ -0,0 +1,44 @@
+using System;
+using System.IO;
+using Mono.Terminal;
+
+namespace Mal {
+    class step0_repl {
+        // read
+        static string READ(string str) {
+            return str;
+        }
+
+        // eval
+        static string EVAL(string ast, string env) {
+            return ast;
+        }
+
+        // print
+        static string PRINT(string exp) {
+            return exp;
+        }
+
+        // REPL
+        static string RE(string env, string str) {
+            return EVAL(READ(str), env);
+        }
+
+        static void Main(string[] args) {
+            string prompt = "user> ";
+            LineEditor lineedit = new LineEditor("Mal");
+
+            while (true) {
+                string line;
+                try {
+                    line = lineedit.Edit(prompt, "");
+                    if (line == null) { break; }
+                } catch (IOException e) {
+                    Console.WriteLine("IOException: " + e.Message);
+                    break;
+                }
+                Console.WriteLine(PRINT(RE(null, line)));
+            }
+        }
+    }
+}