WebFund 2015W Lecture 10 - Revision history

Soma: /* Notes */

2015-02-09T17:14:05Z

Notes

@@ Line 9: / Line 9: @@
 ==Notes==
 <h3>Breaking a few things in notes-demo</h3>
@@ Line 118: / Line 147: @@
    </li>
 </ul>
 <h3>Adding tags in notes-demo</h3>

Soma: /* CORRECTION regarding hasOwnProperty() */

2015-02-09T16:02:01Z

CORRECTION regarding hasOwnProperty()

← Older revision		Revision as of 16:02, 9 February 2015
Line 132:		Line 132:

	<pre>		<pre>
	if (!~~userNotes~~.hasOwnProperty(username)) {		if (!Object.hasOwnProperty(username)) {
	userNotes[username] = [];		userNotes[username] = [];
	}		}

LeeCroft at 05:49, 9 February 2015

2015-02-09T05:49:16Z

← Older revision		Revision as of 05:49, 9 February 2015
Line 6:		Line 6:

	The video from the lecture given on February 4, 2015 is available now [http://homeostasis.scs.carleton.ca/~soma/webfund-2015w/lectures/comp2406-2015w-lec10-04Feb2015.mp4 as an MP4].		The video from the lecture given on February 4, 2015 is available now [http://homeostasis.scs.carleton.ca/~soma/webfund-2015w/lectures/comp2406-2015w-lec10-04Feb2015.mp4 as an MP4].


	==Notes==		==Notes==

LeeCroft at 05:48, 9 February 2015

2015-02-09T05:48:46Z

Show changes

Soma: /* CORRECTION */

2015-02-04T17:45:09Z

CORRECTION

← Older revision		Revision as of 17:45, 4 February 2015
Line 9:		Line 9:
	==Notes==		==Notes==

	===CORRECTION===		===CORRECTION regarding hasOwnProperty()===

	In lecture we saw that we could break notes-demo by giving <tt>hasOwnProperty</tt> as a username. This error is because the following code in the login post handler is incorrect:		In lecture we saw that we could break notes-demo by giving <tt>hasOwnProperty</tt> as a username. This error is because the following code in the login post handler is incorrect:
Line 30:		Line 30:

	Note you can create an object x with no prototype by doing the following:		Note you can create an object x with no prototype by doing the following:
			<pre>
			x = Object.create(null);
			</pre>
			However, this is not normally done. Indeed, even if you use a JSON parser objects will have a non-null prototype.

			Thus, use hasOwnProperty()!

Soma: /* CORRECTION */

2015-02-04T17:43:25Z

CORRECTION

← Older revision		Revision as of 17:43, 4 February 2015
Line 21:		Line 21:
	This code should instead say:		This code should instead say:

	<~~source lang="javascript" enclose="div"~~>		<pre>
	if (!userNotes.hasOwnProperty(username)) {		if (!userNotes.hasOwnProperty(username)) {
	userNotes[username] = [];		userNotes[username] = [];
	}		}
	</~~source~~>		</pre>

	If you are treating a JavaScript object as an associative array you must explicitly check whether a given key value (property) is present using the hasOwnProperty() method inherited by every object.		If you are treating a JavaScript object as an associative array you must explicitly check whether a given key value (property) is present using the hasOwnProperty() method inherited by every object.

	Note you can create an object x with no prototype by doing the following:		Note you can create an object x with no prototype by doing the following:

Soma: /* CORRECTION */

2015-02-04T17:43:13Z

CORRECTION

← Older revision		Revision as of 17:43, 4 February 2015
Line 13:		Line 13:
	In lecture we saw that we could break notes-demo by giving <tt>hasOwnProperty</tt> as a username. This error is because the following code in the login post handler is incorrect:		In lecture we saw that we could break notes-demo by giving <tt>hasOwnProperty</tt> as a username. This error is because the following code in the login post handler is incorrect:

	<~~source lang="javascript"~~>		<pre>
	if (!userNotes[username]) {		if (!userNotes[username]) {
	userNotes[username] = [];		userNotes[username] = [];
	}		}
	</~~source~~>		</pre>

	This code should instead say:		This code should instead say:

Soma: /* CORRECTION */

2015-02-04T17:42:14Z

CORRECTION

← Older revision		Revision as of 17:42, 4 February 2015
Line 21:		Line 21:
	This code should instead say:		This code should instead say:

	<source lang="javascript">		<source lang="javascript" enclose="div">
	if (!userNotes.hasOwnProperty(username)) {		if (!userNotes.hasOwnProperty(username)) {
	userNotes[username] = [];		userNotes[username] = [];

Soma: /* Notes */

2015-02-04T17:38:24Z

Notes

← Older revision		Revision as of 17:38, 4 February 2015
Line 8:		Line 8:

	==Notes==		==Notes==

			===CORRECTION===

			In lecture we saw that we could break notes-demo by giving <tt>hasOwnProperty</tt> as a username. This error is because the following code in the login post handler is incorrect:

			<source lang="javascript">
			if (!userNotes[username]) {
			userNotes[username] = [];
			}
			</source>

			This code should instead say:

			<source lang="javascript">
			if (!userNotes.hasOwnProperty(username)) {
			userNotes[username] = [];
			}
			</source>

			If you are treating a JavaScript object as an associative array you must explicitly check whether a given key value (property) is present using the hasOwnProperty() method inherited by every object.

			Note you can create an object x with no prototype by doing the following:

Soma: Created page with "==Resources== * [http://homeostasis.scs.carleton.ca/~soma/webfund-2015w/code/notes-demo.zip notes-demo code] ==Video== The video from the lecture given on February 4, 2015 ..."

2015-02-04T16:38:55Z

Created page with "==Resources== * [http://homeostasis.scs.carleton.ca/~soma/webfund-2015w/code/notes-demo.zip notes-demo code] ==Video== The video from the lecture given on February 4, 2015 ..."

New page

==Resources==
* [http://homeostasis.scs.carleton.ca/~soma/webfund-2015w/code/notes-demo.zip notes-demo code]

==Video==

The video from the lecture given on February 4, 2015 is available now [http://homeostasis.scs.carleton.ca/~soma/webfund-2015w/lectures/comp2406-2015w-lec10-04Feb2015.mp4 as an MP4].

==Notes==