diff --git a/lib/coffee_script/grammar.y b/lib/coffee_script/grammar.y
index 1bbdde76..1a14e4c7 100644
--- a/lib/coffee_script/grammar.y
+++ b/lib/coffee_script/grammar.y
@@ -80,6 +80,7 @@ rule
 
   Block:
     INDENT Expressions OUTDENT        { result = val[1] }
+  | INDENT OUTDENT                    { result = Expressions.new([]) }
   ;
 
   # All tokens that can terminate an expression.
@@ -186,10 +187,7 @@ rule
   # Function definition.
   Code:
     ParamList "=>" Block              { result = CodeNode.new(val[0], val[2]) }
-  | ParamList "=>" Expression         { result = CodeNode.new(val[0], Expressions.new([val[2]])) }
   | "=>" Block                        { result = CodeNode.new([], val[1]) }
-  | "=>" Expression                   { result = CodeNode.new([], Expressions.new([val[1]])) }
-  | "=>"                              { result = CodeNode.new([], Expressions.new([])) }
   ;
 
   # The parameters to a function definition.
@@ -306,7 +304,7 @@ rule
 
   # The while loop. (there is no do..while).
   While:
-    WHILE Expression Block        { result = WhileNode.new(val[1], val[2]) }
+    WHILE Expression Block            { result = WhileNode.new(val[1], val[2]) }
   ;
 
   # Array comprehensions, including guard and current index.
@@ -325,9 +323,9 @@ rule
 
   # The source of the array comprehension can optionally be filtered.
   ForSource:
-    IN Expression                 { result = [val[1]] }
+    IN Expression                     { result = [val[1]] }
   | IN Expression
-    WHEN Expression                  { result = [val[1], val[3]] }
+    WHEN Expression                   { result = [val[1], val[3]] }
   ;
 
   # Switch/When blocks.
@@ -336,8 +334,6 @@ rule
       Whens OUTDENT                   { result = val[3].rewrite_condition(val[1]) }
   | SWITCH Expression INDENT
       Whens ELSE Block OUTDENT        { result = val[3].rewrite_condition(val[1]).add_else(val[5]) }
-  | SWITCH Expression INDENT
-      Whens ELSE Expression OUTDENT   { result = val[3].rewrite_condition(val[1]).add_else(val[5]) }
   ;
 
   # The inner list of whens.
@@ -387,8 +383,8 @@ rule
   # The full complement of if blocks, including postfix one-liner ifs and unlesses.
   If:
     IfBlock IfEnd                     { result = val[0].add_else(val[1]) }
-  | Expression IF Expression        { result = IfNode.new(val[2], Expressions.new([val[0]]), nil, {:statement => true}) }
-  | Expression UNLESS Expression  { result = IfNode.new(val[2], Expressions.new([val[0]]), nil, {:statement => true, :invert => true}) }
+  | Expression IF Expression          { result = IfNode.new(val[2], Expressions.new([val[0]]), nil, {:statement => true}) }
+  | Expression UNLESS Expression      { result = IfNode.new(val[2], Expressions.new([val[0]]), nil, {:statement => true, :invert => true}) }
   ;
 
 end
diff --git a/lib/coffee_script/lexer.rb b/lib/coffee_script/lexer.rb
index 5f5fcbf8..20f227ca 100644
--- a/lib/coffee_script/lexer.rb
+++ b/lib/coffee_script/lexer.rb
@@ -44,6 +44,10 @@ module CoffeeScript
     # Outdents that come before these tokens don't signify the end of the
     # expression. TODO: Is this safe?
     EXPRESSION_TAIL = [:CATCH, :WHEN, :ELSE, ')', ']', '}']
+    
+    # Single-line flavors of block expressions that have unclosed endings.
+    # The grammar can't disambiguate them, so we insert the implicit indentation.
+    SINGLE_LINERS = [:ELSE, "=>"]
 
     # The inverse mappings of token pairs we're trying to fix up.
     INVERSES = {:INDENT => :OUTDENT, :OUTDENT => :INDENT, '(' => ')', ')' => '('}
@@ -250,12 +254,12 @@ module CoffeeScript
     # blocks, so it doesn't need to.
     def add_implicit_indentation
       scan_tokens do |prev, token, post, i|
-        if token[0] == :ELSE && post[0] != :INDENT
+        if SINGLE_LINERS.include?(token[0]) && post[0] != :INDENT
           line = token[1].line
           @tokens.insert(i + 1, [:INDENT, Value.new(2, line)])
           loop do
             i += 1
-            if !@tokens[i] || ["\n", ")", :OUTDENT].include?(@tokens[i][0])
+            if !@tokens[i] || @tokens[i][0] == "\n"
               @tokens.insert(i, [:OUTDENT, Value.new(2, line)])
               break
             end
diff --git a/lib/coffee_script/narwhal/coffee-script.coffee b/lib/coffee_script/narwhal/coffee-script.coffee
index 95846c94..0d57256e 100644
--- a/lib/coffee_script/narwhal/coffee-script.coffee
+++ b/lib/coffee_script/narwhal/coffee-script.coffee
@@ -20,7 +20,9 @@ checkForErrors: coffeeProcess =>
 # Run a simple REPL, round-tripping to the CoffeeScript compiler for every
 # command.
 exports.run: args =>
-  return true if args.length
+  if args.length
+    exports.evalCS(File.read(path)) for path in args
+    return true
 
   while true
     try
@@ -46,13 +48,3 @@ exports.compile: source =>
 # Evaluating a string of CoffeeScript first compiles it externally.
 exports.evalCS: source =>
   eval(exports.compile(source))
-
-# Make a factory for the CoffeeScript environment.
-exports.makeNarwhalFactory: path =>
-    code: exports.compileFile(path)
-    factoryText: "function(require,exports,module,system,print){" + code + "/**/\n}"
-    if system.engine is "rhino"
-      Packages.org.mozilla.javascript.Context.getCurrentContext().compileFunction(global, factoryText, path, 0, null)
-    else
-      # eval requires parentheses, but parentheses break compileFunction.
-      eval("(" + factoryText + ")")
diff --git a/lib/coffee_script/narwhal/lib/coffee-script.js b/lib/coffee_script/narwhal/lib/coffee-script.js
index 9677a324..0b63db0e 100644
--- a/lib/coffee_script/narwhal/lib/coffee-script.js
+++ b/lib/coffee_script/narwhal/lib/coffee-script.js
@@ -18,8 +18,15 @@
   // Run a simple REPL, round-tripping to the CoffeeScript compiler for every
   // command.
   exports.run = function(args) {
-    var result;
+    var __a, __b, __c, __d, path, result;
     if (args.length) {
+      __a = args;
+      __d = [];
+      for (__b=0, __c=__a.length; __b<__c; __b++) {
+        path = __a[__b];
+        __d[__b] = exports.evalCS(File.read(path));
+      }
+      __d;
       return true;
     }
     while (true) {
@@ -53,16 +60,4 @@
   exports.evalCS = function(source) {
     return eval(exports.compile(source));
   };
-  // Make a factory for the CoffeeScript environment.
-  exports.makeNarwhalFactory = function(path) {
-    var code, factoryText;
-    code = exports.compileFile(path);
-    factoryText = "function(require,exports,module,system,print){" + code + "/**/\n}";
-    if (system.engine === "rhino") {
-      return Packages.org.mozilla.javascript.Context.getCurrentContext().compileFunction(global, factoryText, path, 0, null);
-    } else {
-      // eval requires parentheses, but parentheses break compileFunction.
-      return eval("(" + factoryText + ")");
-    }
-  };
 })();
\ No newline at end of file
diff --git a/lib/coffee_script/narwhal/lib/coffee-script/loader.js b/lib/coffee_script/narwhal/lib/coffee-script/loader.js
index 1a79dbbb..609385a7 100644
--- a/lib/coffee_script/narwhal/lib/coffee-script/loader.js
+++ b/lib/coffee_script/narwhal/lib/coffee-script/loader.js
@@ -6,13 +6,15 @@
   };
   loader = {
     // Reload the coffee-script environment from source.
-    reload: function(topId, path) {
+    reload: function(topId) {
       coffeescript = coffeescript || require('coffee-script');
-      return (factories[topId] = coffeescript.makeNarwhalFactory(path));
+      return (factories[topId] = function() {
+        return coffeescript;
+      });
     },
     // Ensure that the coffee-script environment is loaded.
-    load: function(topId, path) {
-      return factories[topId] = factories[topId] || this.reload(topId, path);
+    load: function(topId) {
+      return factories[topId] = factories[topId] || this.reload(topId);
     }
   };
   require.loader.loaders.unshift([".coffee", loader]);
diff --git a/lib/coffee_script/narwhal/loader.coffee b/lib/coffee_script/narwhal/loader.coffee
index ccdcacbf..e55f7ba7 100644
--- a/lib/coffee_script/narwhal/loader.coffee
+++ b/lib/coffee_script/narwhal/loader.coffee
@@ -6,13 +6,13 @@ factories: {}
 loader: {
 
   # Reload the coffee-script environment from source.
-  reload: topId, path =>
+  reload: topId =>
     coffeescript ||= require('coffee-script')
-    factories[topId]: coffeescript.makeNarwhalFactory(path)
+    factories[topId]: => coffeescript
 
   # Ensure that the coffee-script environment is loaded.
-  load: topId, path =>
-    factories[topId] ||= this.reload(topId, path)
+  load: topId =>
+    factories[topId] ||= this.reload(topId)
 
 }
 
diff --git a/lib/coffee_script/nodes.rb b/lib/coffee_script/nodes.rb
index 5aa5d277..82077906 100644
--- a/lib/coffee_script/nodes.rb
+++ b/lib/coffee_script/nodes.rb
@@ -693,8 +693,8 @@ module CoffeeScript
     end
 
     # Rewrite a chain of IfNodes to add a default case as the final else.
-    def add_else(expressions)
-      chain? ? @else_body.add_else(expressions) : @else_body = expressions.unwrap
+    def add_else(exprs)
+      chain? ? @else_body.add_else(exprs) : @else_body = (exprs && exprs.unwrap)
       self
     end