Al Hoang

Apress released a book titled Practical Ocaml and while I was excited about the book and read the interview with the author. However, after looking briefly through the comments on Lambda the Ultimate I might have to reconsider purchasing this book.

Ehud comments:
I haven’t seen the book yet, but it’s really sad if the book is as problematic as this thread indicates. I had high hopes for the “Practical X” line of books. I thought it might become an O’reilly-like brand for books about non-mainstream language

Matt comments :
This book is a big disappointment. As already noted, it has some severe stylistic problems and the writing is uninspiring, to say the least. But by far the worst problem is that the author’s knowledge of his subject is simply insufficient. This shows up all over the place, but I’ll highlight two examples that I think exemplify the issue.

William comments :
Some items are given only a superficial introduction (e.g. variants — a very important part of OCaml), and then used fairly heavily two chapters later without so much as a pointer back to their introduction for people skimming the book.

and finally Merjis (one of the technical reviewers) writes on his blog :
I only wrote one candid assessment, and decency and privacy prevent me from disclosing what was in it. I will just say that it was not positive.

Needless to say, a very disappointing round of comments. The part regarding poor introduction of material then abusing it later on is a serious flaw in my assessment of the book. I have been suffering this problem for years on many different topics (maybe it’s just because I’m brain damaged) and it’s one of the major things I always am critical about when evaluating the learning process on anything. Crappy treatment of the foundations you are trying to build the rest of your mental model on is terrible.

Related

• A Lambda the Ultimate contributers view on Ocaml the language itself is available here
• A much better (and free) introduction to Ocaml (supposedly) is available here

I just took a glance at

photosynch and

am really impressed with the applications of computer vision and image

processing techniques to create a really unique application.

The basic

idea is to take a pile of photos that are related to each other somehow

(imagine taking zillions of pictures of the Taj Mahal from tons of

different places) find similar features in all the images and try to

reconstruct a mock 3d space that shows the spacial relation between

all of your photos. This is really cool as you might be able to create

a very interesting photo tour from your photo collection in a 3d

navigatable space.

Oddly, I was trying to come up with a similar idea to link videos stills

in QuickTimeVR movies and try to use the linkable features in QuicktimeVR

to provide clickable hotspots that would take you to another photo that

was a picture of the same scene however this is far slicker and if it works

with very little intervention from the user besides pointing to a pile

of photos and letting it do its job that would be great.

However, there are still caveats. The whole process takes hours or days

to currently do and the current technology preview is only for a pre-rendered

project. The true acid test will be in my opinion the ability to

just point to a folder of pictures and have it do its job with as little

possible human intervention as possible. That is a not a trivial problem

but I’m sure we’ll see something interesting especially since it has

two (very well)

known researchers

in the computer vision field. I’m really looking forward to the results

of their labor. My last question is how many technologies behind this

are patented already. It’d be great if it an OSS implementation inspired

from this project could be made however patents are a sticky problem.

Try it yourself

( 6 or 7 REQUIRED)

I noticed Charles Nutter (one of the JRuby developers) mentioning that the fork() method in JRuby will most not likely be supported:

We would strongly prefer to avoid any implementation that requires fork, since we can’t really support fork in JRuby.

While I can understand the difficulties in the Java VM giving lots of hell trying to handle something like fork() I feel it’s a shame since it means if you use fork and quite a few process related calls in Ruby it will not be portable in JRuby. For a sysadmin, handling processes is one of their jobs so personally, I hope they can come up with some way to handle it somehow. But JRuby’s strengths might not be in a scripting language for sys admins but providing a way to integrate rails with the monster that is J2EE. How cool would it be to develop a rails application all in the context of a java web application that you can just deploy right into a Java application server? I think this could be JRuby’s little nitch (besides being an integration tool for java devs)

More here