From aeb35a15e8bba29376ff3843a6236b505cf38331 Mon Sep 17 00:00:00 2001
From: Dominic Chambers <dominic.chambers@gmail.com>
Date: Sat, 25 Oct 2014 21:44:31 +0100
Subject: [PATCH] Optimized the most common use-case likely with Topiarist
 (verifying arguments using isA()) so that it's now ~2.5 times slower than
 doing the same check manually, rather than being ~25 times slower, as was the
 case before. To achive this I did have to relax the argument checking
 performed, but this actuallly resulted in the browser throwing a clearer
 error message than what Topiarist was producing anyway.

---
 lib/topiarist.js | 12 +++++-------
 package.json     |  2 +-
 spec/IsASpec.js  |  4 ++--
 3 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/lib/topiarist.js b/lib/topiarist.js
index 7318365..3924157 100644
--- a/lib/topiarist.js
+++ b/lib/topiarist.js
@@ -398,19 +398,17 @@
 	 *  or is null, false otherwise.
 	 */
 	function isA(instance, parent) {
+		if(instance == null) {
+			return false;
+		}
+
 		// sneaky edge case where we're checking against an object literal we've mixed in or against a prototype of
 		//  something.
 		if (typeof parent === 'object' && parent.hasOwnProperty('constructor')) {
 			parent = parent.constructor;
 		}
 
-		assertArgumentOfType('function', parent, ERROR_MESSAGES.NOT_CONSTRUCTOR, 'Parent', 'isA');
-
-		if (instance == null) {
-			return false;
-		}
-
-		if (instance instanceof parent) {
+		if((instance.constructor === parent) || (instance instanceof parent)) {
 			return true;
 		}
 
diff --git a/package.json b/package.json
index 6d4f1a8..d47a898 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
 	"name": "topiarist",
-	"version": "0.1.0",
+	"version": "0.1.1",
 	"author": "kybernetikos <kybernetikos@gmail.com>",
 	"description": "Topiarist provides tree and shape-based type verification for JavaScript.",
 	"main": "./lib/topiarist.js",
diff --git a/spec/IsASpec.js b/spec/IsASpec.js
index ff11fcf..495175b 100644
--- a/spec/IsASpec.js
+++ b/spec/IsASpec.js
@@ -47,7 +47,7 @@ describe("topiarist.isA", function() {
 	it('throws an error if the potential assignee is not a constructor.', function() {
 		expect( function() {
 			topiarist.isA(instance, 34);
-		}).toThrow(err.NOT_CONSTRUCTOR('Parent', 'isA', 'number'));
+		}).toThrow();
 	});
 
 	it('returns false for a null instance.', function() {
@@ -85,4 +85,4 @@ describe("topiarist.isA", function() {
 	it('returns true for an instance and a mixin that was defined without a constructor.', function() {
 		expect( topiarist.isA(instance, ObjMixin)).toBe( true );
 	});
-});
\ No newline at end of file
+});