-In case you haven't already used it, prototype.js is a - JavaScript library written by Sam Stephenson. +In case you haven't already used it, prototype.js is a + JavaScript library written by Sam Stephenson. This amazingly well thought and well written piece of standards-compliant code takes a lot of the burden associated with creating rich, highly interactive web pages that characterize the Web 2.0 off your back.
@@ -20,7 +20,7 @@ In case you haven't already used it, prototAs you read the examples and the reference, developers familiar with the Ruby - programming language will notice an intentional similarity between Ruby's + programming language will notice an intentional similarity between Ruby's built-in classes and many of the extensions implemented by this library.
@@ -32,7 +32,7 @@ In case you haven't already used it, protot- Unlike the DOM function, though, this one goes further. You can pass more than one id and + Unlike the DOM function, though, this one goes further. You can pass more than one id and $() will return an Array object with all the requested elements. The example below should illustrate this.
@@ -76,7 +76,7 @@ function test2()- The $F() function is a another welcome shortcut. It returns the value of any field input control, + The $F() function is a another welcome shortcut. It returns the value of any field input control, like text boxes or drop-down lists. The function can take as argument either the element id or the element object itself.
- This function, combined with the extensions for the Array class, - makes it easier to convert or copy any enumerable list into an - Array object. One suggested use is to convert DOM + This function, combined with the extensions for the Array class, + makes it easier to convert or copy any enumerable list into an + Array object. One suggested use is to convert DOM NodeLists into regular arrays, which can be traversed more efficiently. See example below.
@@ -113,8 +113,8 @@ function test3() - - + +- This <a href="http://othersite.com/page.html">text</a> has - a <a href="#localAnchor">lot</a> of - <a href="#otherAnchor">links</a>. Some are + This <a href="http://othersite.com/page.html">text</a> has + a <a href="#localAnchor">lot</a> of + <a href="#otherAnchor">links</a>. Some are <a href="http://wherever.com/page.html">external</a> and some are <a href="#someAnchor">local</a>
-@@ -309,21 +309,21 @@ function showLocalLinks(paragraph)
I used to find myself writing a lot of for loops. Although, -Prototype doesn’t by any means eliminate the need to do for loops, +
I used to find myself writing a lot of for loops. Although,
+Prototype does not by any means eliminate the need to do for-loops,
it does give you access to what I consider to be a cleaner, easier to read method in each.
The each function takes one argument, an iterator function. -This iterator is invoked once for every item in the array, and that item -along with the optional index is passed to the iterator. So if +
The each function takes one argument, an iterator function. +This iterator is invoked once for every item in the array, and that item +along with the optional index is passed to the iterator. So if we also needed the index we could do something like the code below.
Hashes can be created by wrapping an Object (associative array) in +
Hashes can be created by wrapping an Object (associative array) in $H() and can have their key/value pairs exposed.
The collect function allows you to iterate over an Array and return the -results as a new array. Each item returned as a result of the iteration will be +
The collect function allows you to iterate over an Array and return the +results as a new array. Each item returned as a result of the iteration will be pushed onto the end of the new array.
You can even join on the end of the block.
The include function allows you to check if a value is included in an array -and returns true or false depending on if a match was made. Assuming I put -up a form asking the user to name some artist in my iTunes playlist, +
The include function allows you to check if a value is included in an array +and returns true or false depending on if a match was made. Assuming I put +up a form asking the user to name some artist in my iTunes playlist, we could do something like the code below. Prime candidate for some conditional madness.
The inject function is good for getting a collective sum from an array of +
The inject function is good for getting a collective sum from an array of values. For instance, to add up all the numbers.
The first argument to inject is just an initial value that +
The first argument to inject is just an initial value that would be added to the sum, so if we added 1 instead of 0, the output would be 162.
-When given an Array, the findAll function will return an array of -items for which the iterator evaluated to true. Basically, it allows you to -build a new array of values based on some search criteria. -If we wanted to find all products whose type was “E-Commerce” +When given an Array, the findAll function will return an array of +items for which the iterator evaluated to true. Basically, it allows you to +build a new array of values based on some search criteria. +If we wanted to find all products whose type was “E-Commerce” we could do something like the code below.
Note that even if only one match is made, just as in this case, -the result is still returned as an array. In that case, +
Note that even if only one match is made, just as in this case, +the result is still returned as an array. In that case, ecom.company would return undefined.
Unlike the findAll function, the detect function will only -return the first item for which the expression inside -the iterator is true. So, if we wanted to find the first number that +
Unlike the findAll function, the detect function will only +return the first item for which the expression inside +the iterator is true. So, if we wanted to find the first number that was greater than 5 we’d do something like the code below.
Even though, there are other numbers above 5 in our array, detect +
Even though, there are other numbers above 5 in our array, detect only gives us the first match back.
The invoke function allows us to pass a method as a string and -have that method invoked. For instance, if we wanted to sort +
The invoke function allows us to pass a method as a string and +have that method invoked. For instance, if we wanted to sort our array of artists we’d do something like this:
Why not just use F.Artists.sort? Well, for the example above +
Why not just use F.Artists.sort? Well, for the example above we could do just that, but here is where invoke shines.
The reason this will not work is because it is taking each item -in that array and trying to apply sort to it, thus if we wrote it outright, +
The reason this will not work is because it is taking each item +in that array and trying to apply sort to it, thus if we wrote it outright, it would look something like this:
-Now, what about passing arguments to the invoke function? -The first argument passed to invoke is the method to be invoked, +Now, what about passing arguments to the invoke function? +The first argument passed to invoke is the method to be invoked, and any other arguments beyond that will be passed as arguments to the invoked method.