Libraries

Two approaches

1. Understand how the library works and use it to save time and effort.
2. Use a library like a black box that you dare not mess with.

Like any tool, a library could be used for good or for evil.

Prototype

• Lots of useful shortcuts, including Ajax
• Clean code, quite lightweight
• Little or no documentation
• Comes bundled with Rails... but obtrusively

Script.aculo.us

• Built on top of Prototype
• Lots of animations and effects: fades, drag'n'drop, etc.
• DHTML by any other name
• You can cherry pick the files you need
• Ongoing documentation by users

Moo FX

• Like script.aculo.us, built on top of Prototype
• Very lightweight
• Effects built on width, height, and opacity e.g. show/hide, fade, etc.

Rico

• Yet again, built on top of Prototype
• Ajax, animation, and drag'n'drop
• Documentation is sparse and what's there encourages obtrusive JavaScript.

jQuery

• A compressed version is provided to keep the filesize down
• Chainable methods: uses dot syntax to join multiple methods
• Handy for attaching events and some visual effects

Mochikit

• Very well documented
• Quite geeky: borrows ideas from other languages like Python
• You can cherry pick the files you need

Dojo

• Well documented
• Quite complex: it will make most sense to "serious" programmers
• The Ajax functionality uses JSON
• Geared towards creating widgets

Sarissa

• Designed to make parsing XML easier: XSL, XPath, etc.
• Worth investigating if you use XML a lot
• Geeky: not for the faint of heart

Yahoo! UI Library

• Well researched and documented
• Modular
• Also provides widgets (sliders, calendars, etc.)
• Design patterns also open-sourced.

Conclusions

• Choose a library to suit your needs: don't adjust your needs to fit the way a library works.
• If you use a library, understand how it works so that you aren't clueless when something goes wrong.
• Remember the end user: a library might make your life easier, but at what cost? (filesize, browser compatibility, etc.).

Thank you