Train of Thought

OpenID has been in the news lately. Having decided to get myself one, I discovered I already had ready access to two:

• Technorati
• Yahoo (I had to ask them to create it)

However, one of the points of OpenID is that no central servers are needed, and I could host my own. So I read Sam Ruby’s guide, which covered the essential details, and had a go. jh.mcaleely.com has three core components:

• An openid server (at /idservice) currently running phpMyID v0.7
• A Yadis/xrdf description of my local ID and the two others which are also me.
• A HTML page at the same location which is intended to help OpenID clients which don’t use xrdf to find my ID.

One key thing I discovered is that clients which use the HTML are quite sensitive about their parsing. plaxo.com, for example, would not parse a HTML4.01/Transisitional document, but was happy with the same document in XHTML 1.0. Given this sensitivity, I’m not hosting any actual human readable content at the URL - just a redirect to my homepage.What can I do with my OpenID? Join plaxo.com without a new password to remember for starters. I don’t think I would have bothered otherwise. I can also use it to log on to this wordpress blog. As I add blogs to mcaleely.com, I don’t have to add passwords.

I still haven’t figured out what to use the sidebar/blogroll for - Liam’s looking quite lonely there. Is it something for my convenience, or is it for the audience of this blog? Who is that audience?

Anyway, while I figure that one out, here’s a few things I read regularly. The order is not significant:

• Edward Tufte - Ask ET: Discussions about information display and design.
• Slashdot: Geeks at work and play.
• Dan Bricklin: Blogger on software
• Joel On Software: Blogger on software.
• Andrew Sullivan: Blogging from a conservative gay Catholic in NY.
• The Old New Thing: Something interesting about Win32 every day.
• Dilbert: The cartoon.
• Madam and Eve: A cartoon from South Africa my brother introduced me to.
• Adam and Andy: Cartoon about a couple somewhere in the US.
• Doonesbury: A habit from my stint in the US.
• Rands In Repose: Thoughts on software management, and Vegas!
• Scripting News: Blogging on tech stuff. The first one I started reading!
• Schneier on Security: Readable thoughts on security (usually of computers).
• Steve Miller’s CultureWatch: A survey of thoughts and essays from the libertarian wing of gay culture.
• The Cycling feed from the BBC

A mixed bunch, but a few themes and stereotypes are there to be observed :-)

A blog posting especially for Adrian, now of Macrobug, apparently. He tells me I don’t post here often enough…

Ok, so I’ve made it up to chapter 18 of my book, and I’m still enjoying the read. There was a brief diversion while the book chased the illusion of an OS/filesystem independent file naming library, but it’s keeping me entertained.

Perhaps by working for another OS company, the dream of unifying the various Unix & Win32 filesystems seems less important to me. Better really to give in, and recognise that the file namespace is the domain of the OS/filesystem/user, and there are too many leaks in abstractions above them.

Anyway, the title of this post is why not Lisp - putting aside my reservations of yesterday - why isn’t it more popular? There are the many reasons noted by Paul Graham, but there is a more prosaic one that hit me when I started.

There is no implementation that seems reasonable to use!

On my chosen OS (Mac OS X at the moment) I have the grand choice of three commercial implementations, and four open source implementations. All seem to have a significant gotcha.

Only one of the commercial implementations appears to have a ‘free redistribution’ model, the other two want some percentage or down payment from the sales of any product I create. Yuk.

Of the open source implementations, none are complete enough to host all of the examples from the book I’m using to learn the language. Some lack threads (hello - this is 2006), and others lack Unicode (hello - wave if you don’t speak ASCII English).

Whether the royalty free commercial implementation supports the features needed by the book is not clear (great sales pitch!). The book’s author recommends a vendor without a price list, which I assume to mean they’re in the we-want-a-percentage camp.

For any more popular language there is usually a bit more choice and competition among the tools vendors. As I see it, on Mac OS X, there isn’t a clear ‘one stop shop’ implementation I can choose to: learn the language with a popular text, and then distribute my first few applications ‘for free’. The situation on Win32 doesn’t look much rosier, although I’ve not looked at the details.

No wonder no-one is using Lisp.

Prompted by a book I borrowed from a friend, I’ve decided to learn Lisp.

Many years ago, the first programming course on my degree was in a language similar to Lisp (that I now forget), and I thoroughly enjoyed using it. MacLisp was also around on campus, for use in ‘maths stuff’. Not being a mathematician, I ignored that.

Both experiences made me write off lisp (and similar brethren) as a practical language - they seemed too small, too focussed on things like recursion that aren’t all that useful on constrained systems.

However, there’s a famous quote around that notes that everyone should learn Lisp, if only for the experience, and the write up in Hackers and Painters persuaded me to have a go.

So far, I’m up to chapter 15 in ‘Practical Common Lisp‘, and I think I may be hooked!