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One page: Javascript in 10 minutes

javascript.infogami.com

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Re: One page: Javascript in 10 minutes

#2

Post by chrisbroadfoot » 

  Property Maps

  var emptyMap = {};
In JavaScript, these are called Objects. I don't think it's right for them to be called "property maps" in a tutorial like this.

The heading called "Objects" should be renamed something like "Constructors" too.

Also, using

  for (var i in array)
is not the preferred way of iterating over an array (the for construct does not guarantee ordering).

Re: One page: Javascript in 10 minutes

#3

Post by user24 »

chrisbroadfoot wrote: post #2

Property Maps var emptyMap = {}; In JavaScript, these are called Objects. I don't think it's right for them to be called "property maps" in a tutorial like this. The heading called "Objects" should be renamed something like "Constructors" too. Also, using for (var i in array) is not the preferred way of iterating over an array (the for construct does not guarantee ordering).

for...in loops also have the drawback of iterating over inherited properties. eg if I extended the prototype of Array with some method, then for...in would iterate over that method too.

traditional for loops incrementing until length is reached are preferable for arrays (personal style: for(var i=0,l=array.length ; iFor objects, for...in with a hasOwnProperty check is preferred, I think (if you're going to be iterating over objects that is, which usually means you're using an object as a textually-indexed array, which isn't that great).

Over all a nice introduction though.

Re: One page: Javascript in 10 minutes

#5

Post by martinkallstrom »

Although I thoroughly appreciate the intent of this introductory page, a really bad way of teaching something to the neophyte is to lead with examples of what NOT to do. If they are to appear at all the place for them is far, far down at the page when all the good examples of what to do has been understood and memorized.

Also, the author should probably put something at the top stating who the introduction is intended for. It is clear to me that it is not for newbie programmers, but that would not be clear to the actual newbie.

A beginner could very well set out thinking that this is the perfect introduction to programming for them. And then in the first paragraph discover the semantically very rich phrase "Javascript is a dynamically typed language". To a programmer that is valuable information but to the beginner it just confusing.

Re: One page: Javascript in 10 minutes

#6

Post by InclinedPlane »

martinkallstrom wrote: post #5

Although I thoroughly appreciate the intent of this introductory page, a really bad way of teaching something to the neophyte is to lead with examples of what NOT to do. If they are to appear at all the place for them is far, far down at the page when all the good examples of what to do has been understood and memorized. Also, the author should probably put something at the top stating who the introduction is intende…

Don't do what Johnny Don't does. Huh?

The best method of teaching, in my experience, is to start with the fundamentals (a skeleton model at a high level of abstraction) even if it's not fully accurate and then fill in the details and all of the cautionary advice bit by bit, building up the skeleton model into a more robust and full featured model.

Re: One page: Javascript in 10 minutes

#7

Post by bootload »

InclinedPlane wrote: post #6
martinkallstrom wrote: post #5

Although I thoroughly appreciate the intent of this introductory page, a really bad way of teaching something to the neophyte is to lead with examples of what NOT to do. If they are to appear at all the place for them is far, far down at the page when all the good examples of what to do has been understood and memorized. Also, the author should probably put something at the top stating who the introduction is intende…

Don't do what Johnny Don't does. Huh? The best method of teaching, in my experience, is to start with the fundamentals (a skeleton model at a high level of abstraction) even if it's not fully accurate and then fill in the details and all of the cautionary advice bit by bit, building up the skeleton model into a more robust and full featured model.

"... Don't do what Johnny Don't does. ..."

Love that Simpson quote, "Boy-Scoutz 'n the Hood" S5E8 ~ http://en.wikipedia.org/wiki/Boy-Scoutz_%27n_the_Hood

Re: One page: Javascript in 10 minutes

#9

Post by dools »

bootload wrote: post #7
InclinedPlane wrote: post #6

Earlier quoted context omitted.

Don't do what Johnny Don't does. Huh? The best method of teaching, in my experience, is to start with the fundamentals (a skeleton model at a high level of abstraction) even if it's not fully accurate and then fill in the details and all of the cautionary advice bit by bit, building up the skeleton model into a more robust and full featured model.

"... Don't do what Johnny Don't does. ..." Love that Simpson quote, "Boy-Scoutz 'n the Hood" S5E8 ~ http://en.wikipedia.org/wiki/Boy-Scoutz_%27n_the_Hood

Except it's actually "Donny Don't" :)

Re: One page: Javascript in 10 minutes

#10

Post by rb2k_ »

Another interesting introduction I can recommend was written by a friend of mine. It focuses more on the semantic differences to other languages (e.g. prototype based inheritance) as to the syntax:

Javascript for people who are in a hurry:

http://kaijaeger.com/javascript-for-people-who-are-in-a-hurr...

Javascript for people who are in slightly less of a a hurry:

http://kaijaeger.com/articles/javascript-for-people-who-are-...

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