added the instanceof operator to the grammar as an operation node

lib/coffee_script/grammar.y

@@ -10,8 +10,8 @@ token TRY CATCH FINALLY THROW
 token BREAK CONTINUE
 token FOR IN WHILE
 token SWITCH WHEN
+token DELETE INSTANCEOF
 token SUPER
-token DELETE
 token NEWLINE
 token COMMENT
 token JS
@@ -27,7 +27,7 @@ prechigh
   right    '==' '!=' IS AINT
   left     '&&' '||' AND OR
   right    '-=' '+=' '/=' '*='
-  right    DELETE
+  right    DELETE INSTANCEOF
   left     "."
   right    THROW FOR IN WHILE NEW
   left     UNLESS IF ELSE
@@ -185,6 +185,7 @@ rule
   | Expression '&&:' Expression       { result = OpNode.new(val[1], val[0], val[2]) }
 
   | DELETE Expression                 { result = OpNode.new(val[0], val[1]) }
+  | Expression INSTANCEOF Expression  { result = OpNode.new(val[1], val[0], val[2]) }
   ;
 
   # Function definition.

lib/coffee_script/lexer.rb

@@ -15,7 +15,7 @@ module CoffeeScript
                   "for", "in", "while",
                   "switch", "when",
                   "super",
-                  "delete"]
+                  "delete", "instanceof"]
 
     # Token matching regexes.
     IDENTIFIER = /\A([a-zA-Z$_]\w*)/

test/fixtures/execution/keyword_operators.cs

@@ -0,0 +1,10 @@
+a: 5
+atype: typeof(a)
+
+b: "hello"
+btype: typeof(b)
+
+Klass: => .
+k: new Klass()
+
+print(atype is 'number' and btype is 'string' and k instanceof(Klass))

test/fixtures/execution/keyword_operators.js

@@ -0,0 +1,10 @@
+(function(){
+  var a = 5;
+  var atype = typeof(a);
+  var b = "hello";
+  var btype = typeof(b);
+  var Klass = function() {
+  };
+  var k = new Klass();
+  print(atype === 'number' && btype === 'string' && k instanceof Klass);
+})();