load-file: accept empty file or final comment, return nil

[jackhill/mal.git] / dart / step6_file.dart

diff --git a/dart/step6_file.dart b/dart/step6_file.dart
index d4e5fb3..3fee92d 100644 (file)
--- a/dart/step6_file.dart
+++ b/dart/step6_file.dart
@@ -20,7 +20,7 @@ void setupEnv(List<String> argv) {
 
   rep('(def! not (fn* (a) (if a false true)))');
   rep("(def! load-file "
-      "(fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))");
+      "(fn* (f) (eval (read-string (str \"(do \" (slurp f) \"\nnil)\")))))");
 }
 
 MalType READ(String x) => reader.read_str(x);
@@ -134,20 +134,7 @@ MalType EVAL(MalType ast, Env env) {
 String PRINT(MalType x) => printer.pr_str(x);
 
 String rep(String x) {
-  var parsed;
-  try {
-    parsed = READ(x);
-  } on reader.ParseException catch (e) {
-    return e.message;
-  }
-
-  var evaledAst;
-  try {
-    evaledAst = EVAL(parsed, replEnv);
-  } on NotFoundException catch (e) {
-    return "'${e.value}' not found";
-  }
-  return PRINT(evaledAst);
+  return PRINT(EVAL(READ(x), replEnv));
 }
 
 const prompt = 'user> ';
@@ -164,6 +151,15 @@ main(List<String> args) {
     var output;
     try {
       output = rep(input);
+    } on reader.ParseException catch (e) {
+      stdout.writeln("Error: '${e.message}'");
+      continue;
+    } on NotFoundException catch (e) {
+      stdout.writeln("Error: '${e.value}' not found");
+      continue;
+    } on MalException catch (e) {
+      stdout.writeln("Error: ${printer.pr_str(e.value)}");
+      continue;
     } on reader.NoInputException {
       continue;
     }