Notes on codes, projects and everything
This post continued from this post. Finally I have found some time to start developing my pet project using Zend Framework. After getting the controller to work the way I am more familiar (comparing to Kohana which I used at work) with, the next step is to get it to output some data.
Traversing a tree structure often involves writing a recursive function. However, Python isn’t the best language for this purpose. Therefore I started flattening the tree into a key-value dictonary structure. Logically it is still a tree, but it is physically stored as a dictionary. Therefore it is now easier to write a simple loop to traverse it.
As the name implies, Resource Definition Framework, or RDF in short, is a language to represent information about resources in world wide web. Information that can be represented is mostly metadata like title (assuming the resource is a web-page), author, last modified date etc. Besides representing resource that is network-accessible, it can be used to represent things that cannot be accessed through the network, as long as it can be identified using a URI.
Often times one would have to write code to evaluate logical statements. For example, given statement p and q, what is p implies q? As there’s no operator for implication in PHP, one would have to rewrite the statement that consists only in NOT (!
), AND (&&
) and OR (||
) operators. When there are a huge load of these statements, code can be difficult to read.
After being frustrated of not getting consistent and accurate result via standard DOM methods especially html_element.getAttribute('key');
and html_element.setAttribute('key', 'value');
, I came across some YUI library components that provides abstractions to various DOM methods. Some interesting DOM-related tools covered in this post are YAHOO.util.Element
, YAHOO.util.DOM
and YAHOO.util.Selector
.
While JSON is a fine data-interchange format, however it does have some limitations. It is well-known for its simplicity, that even a non-programmer can easily compose a JSON file (but humanity will surprise you IRL). Therefore, it is found almost everywhere, from numerous web APIs, to geospatial data (GeoJSON), and even semantic web (RDF/JSON).