jQuery – Page 12 – Weapon of Choice

2006-10-04

jQuery: API documentation /3

Still about improving the official documentation.
|modified content, my style – snapshot for jQuery $( String, Object )
|official content, my style – snapshot for jQuery $( String, Object )
|official content & style – snapshot for jQuery $( String, Object )

Examples on a common ground
The use cases in a software documentation are very important. And as a general principle, the more they are standardized around some basic concepts, the more useful they are, because the reader can easily tell the differences and concentrate on them. As much as possible the differences should be limited to what is special about the functionality being described.

An examples element in the documentation XML has 5 (sub)elements: desc, code, comment, before, after. The answer to why I added the comment element is given below.
The labels for an example subelements (as they now appear in my working sample) are: Example, Solution, Comment, Before, and After (respectively)
Example must be a description of a problem to solve, and I chose to begin it with a “To” + infinitive form, because this is the standard for problems at school; it’s not required that the functionality be central to it. A real and bigger example is preferable to a shorter but artificial one. The same example used over and over, either for showing different solutions or different functionalities should be good, because of the standard effect. Different solutions should be referenced one from the others.
Solution must be limited to the jQuery code excerpt that solves the problem; and it should be complete, so that it could be introduced in the usual framework as is, and produce the After when applied to the Before
Comment can be anything worth to note about the Solution, and the other elements. Less noise, the better. However this is the preferred space for all that is not strictly a problem or solution description. Really the Comment exists for segregating the talk from the data.
Before must be the test context to which the solution is applied, better if represented by a meaningful HTML excerpt.
After must be the Before context as changed by the application of the solution, better if represented by a meaningful HTML excerpt.
Before and After should work together, and the result of their comparison should look like a diff result.
Before and After should also provide context for themselves. That is, <div></div> seems a good choice for a Before but it’s not, beacuse it has no clear context. In fact <body><div></div></body> is much better, because the reader now knows the DOM completely and can make safe assumptions
In general, each functionality should have at least one example, and more often than not, just one example should be fine.
The challenge is to provide a good example where
1. the issue is taken from the real world and is something at which jQuery excels
2. the problem can be cleanly stated and easily understood
3. the solution is short and elegant
4. the comment is short and remarks subtleties to watch out
5. the Before and After are short, clean, and they work side by side in a diff fashion

Highlighting
The Solution, Before and After sections have to show context, but they exist mainly to show how to use the functionality. So I’ve introduced a means for drawing the reader’s attention to what is really important. All the text which in the documentation XML is wrapped by a grave accent (`) is highlighted using a css style.

2006-10-03

jQuery: API documentation /2

Functionality VS function
As an example of something that needs a rewrite take the $ function, which accepts many inputs and mostly does one of two things: either selects a group of elements into a DOM (possibly all of them), or creates a group of elements from scratch.

In the official documentation these two functionalities are mixed up in the filecard with one string argument, whereas the selection functionality with a string argument is split among two filecards, depending on wether there is only one argument for the string or also a second argument for the context. In case of one argument, the functionality does not change because a default value is used for the context.

The signature of a function
A very good thing in the official documentation is the use of type declarations for functions and arguments. Javascript is loosely typed and this is just a handy trick. I think I found a problem related to how much it is used.

The name of a function cannot be adapted in the documentation to reflect its type, so a declaration like Array<Element> get() makes a lot of sense. A different approach is needed for an argument name, which certainly can get a new name in the documentation. For the sake of readers, the same pseudo types should be used as much as possible for arguments as well. In fact, if an argument can get different types without changing the functionality of the function, then it’s much better to use a generic Object type and add a comment than it is to use a more specifiic Element type just because it is the most frequent use of that argument. In the former case the reader gets a hint at a nuance to whatch out, in the latter they need to carefully read the filecard to get the nuance.

The pseudo signature of a function can be augmented also with default values for optional arguments, like other languages do. This improves the readability a bit more, because less words are needed in the documentation, as it is a visual device.

An id for each functionality
Having each functionality documented in its own filecard, a unique identifier for referencing them is then needed. For example, see also the code in 2 could be a short comment of an example in a filecard, where the reader can be made aware of watchouts related to that code. The longer see also the code in ‘jQuery $( String, Object )’ is more informative but would be harder to add in the source of jQuery and to create an hyperlink in the documentation. To implement: longer form automatically built from id

The benefits of an id for each functionality go well beyond that. When speaking or writing about jQuery functions, the use of an id could simplify the reference, though something like calling 32 from 154 causes 9 to hang should definitely be avoided, and for posterity is to be preferred something like (this purely fictitious) calling toggle (32) from oneunload (154) causes serialize (9) to hang (using Rev:123)

For a working sample, I’ve added an id attribute to the method element of the documentation XML. It’s now a decimal number, starting from 1, which I’ve assigned to the most used function of jQuery: jQuery $( String, Object ). For making straighforward the referencing in the documentation XML and hence in the js sources, you simply have to wrap a grave accent (`) around the id of a function, like see also the code in `2`. This works inside the description of a function or example, and inside the comment of an example.

2006-09-292021-10-04

jQuery: API documentation /1

jQuery is pure enjoyment: you try something and it works.

But the jQuery API documentation needs improvements on interface and content.

The interface is a bit annoying, because of the drawer metaphor. The user must always open a drawer to see what’s inside and close it again to tidy up.

This problem affects both the description of a function and the alphabetical grouping of all the functions. So each function description is actually hidden inside two drawers, one for the tab of the first letter of the function name, and the other for the function itself. A bit more complicated than it should be for browsing an API documentation.

Visual jQuery is a replacement of the official interface and content. It’s based on the drawer metaphore as well, but with a twist. The user, knowing what is looking for, imagines a path of predefined categories, and opens all of their drawers to get there. It’s less weird than it seems from this description, but there is some additional problem.

The header eats up almost an half of the vertical space, and it’s not very useful.

Scrolling the page down makes the content disappear under the header.

Any drawer appears at the top, so after opening a drawer at the bottom the user must scroll the page up to see its content.

Simple Style

I’ve just made yet another replacement of the jQuery API documentation.

It’s based on a two columns layout hosting a list of links on the left and the linked content on the right: basic web metaphor.

It’s still far from completion. This is a partial list of what must be done.

add alphabetical positioning for the links on the left; should be something similar to the original alphabetical tabs, just not tabs: clicking on a letter would cause the left pane to scroll
make the functionality the main concept of the documentation and separate functionalities from functions, each in its own filing card: for example, “$( expr )” has now two different functionalities, so they should be represented by two separate filing cards;
add a unique and persistent ID number to each functionality, so that they can be referenced from inside the documentation, and in the wild by means of a an URL ending with this ID; it would appear where now is a #
check the description of any argument; should be very focused about what the function expects, how it’s related to the functionality
add keywords to highlight documentation wide aspects; it would appear where now is the category; should be a comma separated list, with a fixed precedence
check the description, and edit it thinking about the functionality, being very specific on what gets changed and what is returned
find better and useful examples, always involving a DOM context that can be expressed by HTML markup, both in the Before and After sections.
add a comment to a solution, relating it to “synonyms and antonyms”-like solutions
developed at 1024×768 screen resolution using IE6: check others
template adapted to CSS from one generated by Microsoft Word: refine