Very simple nrepl has been added

Makefile

@@ -5,6 +5,9 @@ all:
 repl:
 	./gradlew compileJava && rlwrap java -cp build/classes/java/main/ serene.simple.Main
 
+nrepl:
+	./gradlew compileJava && rlwrap java -cp build/classes/java/main/ serene.simple.Main nrepl
+
 run:
 	./gradlew compileJava && java -cp build/classes/java/main/ serene.simple.Main ${PWD}/test.srns
 

src/main/java/serene/simple/Main.java

@@ -23,6 +23,12 @@ import java.io.IOException;
 import java.io.ByteArrayInputStream;
 import java.io.Console;
 import java.io.FileInputStream;
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.io.StringWriter;
+import java.net.ServerSocket;
+import java.net.Socket;
 
 /**
  * What is missing:
@@ -43,6 +49,9 @@ import java.io.FileInputStream;
  *     sacrificed quality for time.
  */
 public class Main {
+  private static int port = 5544;
+  private static String host = "localhost";
+
   private static String licenseHeader = "\nSerene(simple), Copyright (C) 2019-2020 " +
     "Sameer Rahmani <lxsameer@gnu.org>\n" +
     "Serene(simple) comes with ABSOLUTELY NO WARRANTY;\n" +
@@ -56,6 +65,12 @@ public class Main {
       startRepl();
       return;
     }
+
+    if (args[0].equals("nrepl")) {
+      nrepl();
+      return;
+    }
+
     runSerene(args[0]);
   }
 
@@ -100,6 +115,67 @@ public class Main {
     }
   }
 
+  public static void nrepl() throws IOException {
+    RootScope rootScope = new RootScope();
+    ServerSocket socket = new ServerSocket(Main.port);;
+
+    System.out.println("Serene 'simple' v0.1.0");
+    System.out.println(licenseHeader);
+    System.out.println(
+      String.format("nRepl has been started on tcp://%s:%s", Main.host, Main.port));
+
+    try {
+      Socket clientSocket = socket.accept();
+
+      PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);
+      BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
+
+      while(true) {
+        String inputData = in.readLine();
+
+        if (inputData == null) break;
+
+        ByteArrayInputStream inputStream = new ByteArrayInputStream(inputData.getBytes());
+
+
+        try {
+          ListNode<Node> nodes = Reader.read(inputStream);
+          Object result = ListNode.EMPTY;
+
+          for (Node n : nodes) {
+            result = n.eval(rootScope);
+          }
+
+          if (result == null) {
+            out.println("0nil");
+          }
+          else {
+            out.println(
+              String.format("0%s", result.toString()));
+          }
+
+        }
+        catch(Exception e) {
+          StringWriter sw = new StringWriter();
+          e.printStackTrace(new PrintWriter(sw));
+          String exceptionAsString = sw.toString();
+          out.println(
+            String.format("1%s", exceptionAsString));
+        }
+      }
+
+    }
+    catch (IOException e) {
+      System.out.println("Exception caught when trying to listen on port "
+                         + Main.port + " or listening for a connection");
+      System.out.println(e.getMessage());
+    }
+    finally {
+
+      socket.close();
+    }
+  }
+
   private static void runSerene(String filePath) throws IOException {
     IScope rootScope = new RootScope();
     FileInputStream input = new FileInputStream(filePath);