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Comment: Re: ..that runs on the Java platform. (Score 1) 62

by Per Bothner (#48603471) Attached to: Kawa 2.0 Supports Scheme R7RS
Thanks. Kawa has what one might call "optimistic typing": The compiler calculates the type of an expression, and compares it with the type required by context. It only complains if this intsection is empty. In contrast, in traditional strict typing the compiler requires that expression type be a sub-type of the required type (unless there is an explicit cast). I've thought about adding an option to Kawa (it wouldn't be the default) to implement strict (sub-type) typing. However, that would require various changes and some thought to make palatable.

Comment: Re:How does it compare to Clojure? (Score 2) 62

by Per Bothner (#48591961) Attached to: Kawa 2.0 Supports Scheme R7RS
Ask Rich Hickey that: Kawa (1996) is 11 years older than Clojure (2007).

The linked LWN article meantions some reasons: Among them that Kawa is much faster than closure (both execution speed and start-up speed). Plus some might like that Kawa is mostly-compatible with a pre-existing independently-specified language.

Comment: Re:Traditional (Score 3, Insightful) 62

by Per Bothner (#48591765) Attached to: Kawa 2.0 Supports Scheme R7RS
"Something that I find strange is how fast kawa seems to be [even] in the repl." Note that Kawa does a full compilation (to bytecode), with all the optimizations, even in the repl. (Of course it only optimized one line/command at a time in that case.) The downside is that Kawa is a little fragile if you redefine things in the repl; hence I advise using the --no-inline option for the repl. It's on the list of things to work on when we get a chance.

Comment: Re:Traditional (Score 2) 62

by Per Bothner (#48591663) Attached to: Kawa 2.0 Supports Scheme R7RS
Neither Java or Kawa are "traditional compiled language" in the same sense as C or C++. However, Java as a language (rather than as an implementation technology) is much closer in style to C++ than (say) Python or Ruby. Java has lexical scoping, static name resolution, ahead-of-time compilation (albeit to bytecode), does lots of compile-time error checking. In the current environment, Java (and Scala) are considered closer to "traditional compiled language" than languages like Python or Ruby, which are considered "scripting languages". Of course there is no hard distinction between the two kinds (except marketing) - and Kawa aims at the strengths of both kinds.

Comment: Re:kawa (Score 4, Informative) 62

by Per Bothner (#48591577) Attached to: Kawa 2.0 Supports Scheme R7RS
The Kawa 0.1 interpreter from 1996 was written by Alex Milowski, who is indeed Polish-American.

I took it over in 1996, and re-wrote it as a compiler. At this point, I doubt any of Alex's code still exists. I'm Norwegian-American, and Kawa means nothing in Norwegian. Still, I saw no reason to change the name.

+ - Kawa 2.0 supports Scheme R7RS

Submitted by Per Bothner
Per Bothner (19354) writes "Kawa is a general-purpose Scheme-based programming language that runs on the Java platform. It combines the strengths of dynamic scripting languages (less boiler-plate, fast and easy start-up, a REPL, no required compilation step) with the strengths of traditional compiled languages (fast execution, static error detection, modularity, zero-overhead Java platform integration).

Version 2.0 was just released with many new features. Most notably is (almost) complete support for the latest Scheme specification, R7RS, which was ratified in late 2013. This LWN article contains a brief introduction to Kawa and why it is worth a look."
Data Storage

ZFS Hits an Important Milestone, Version 0.6.1 Released 99

Posted by samzenpus
from the brand-new dept.
sfcrazy writes "ZFS on Linux has reached what Brian Behlendorf calls an important milestone with the official 0.6.1 release. Version 0.6.1 not only brings the usual bug fixes but also introduces a new property called 'snapdev.' Brian explains, 'The snapdev property was introduced to control the visibility of zvol snapshot devices and may be set to either visible or hidden. When set to hidden, which is the default, zvol snapshot devices will not be created under /dev/. To gain access to these devices the property must be set to visible. This behavior is analogous to the existing snapdir property.'"

Comment: Re:texinfo is good for writing documentation (Score 1) 173

by Per Bothner (#42933217) Attached to: GNU Texinfo 5.0 Released
Aside from the fact that it's Just Plain Horrid(TM) to read or write in source format, TexInfo suffers from the same problem that HTML does: No semantics.

You don't seem to know much about Texinfo. It is definitely very much about semantics - quite like DocBook. I agree DocBook takes the semantics thing slightly further than Texinfo - but it has big holes too: For example DocBook doesn't have a standard way to specify the structure of a command/function synopsis except for the C language.

The reason that DocBook is so "verbose" is that it actually indicates what things are.
One reason DocBook is so verbose is because it is XML, which by definition is verbose and human-unfriendly.

I've written plenty of documentation in both Texinfo and DocBook. They're both reasonable formats, but it is clear that DocBook is very tedious if you have to write it "by hand" rather than use a word-processor. Texinfo is much easier to both read and write, and it handles the "semantics" pretty well.

Comment: texinfo is good for writing documentation (Score 2) 173

by Per Bothner (#42932281) Attached to: GNU Texinfo 5.0 Released
Texinfo is is a decent format for writing documentation in - nicer and less verbose than HTML or DocBook. You can generate either HTML or DocBook or XML from Texinfo, and then do a bunch of processing on it. For example the documentation for Kawa is written in texinfo, then makeinfo converts it to docbook, which is then converted to html. The result isn't splashy but (if I say so myself) fairly nice.

Comment: Re:Sometimes not just money (Score 1) 897

by Per Bothner (#39348415) Attached to: How To Crash the US Justice System: Demand a Trial
I honestly hate to go into this because you're right for the most part but most cases in the average metropolitan area have overwhelming evidence.

I'm skeptical, given how frighteningly many cases where someone has been proven innocent after years in prison based on a single eye-witness or jail-house informant, which we know are extremely unreliable, or scientifically bogus evidence, or coerced confessions and plea bargains.

The Internet

Over a Third of the Internet Is Pornographic 247

Posted by samzenpus
from the filthy-web dept.
Th'Inquisitor writes "Pornography makes up 37% of the total number of web pages online, according to a new study published by Optenet, a SaaS provider. According to the report, which looked at a representative sample of around four million extracted URLs, adult content on the Internet increased by 17% in the first quarter of 2010, as compared to the same period in 2009."

Anti-Speed Camera Activist Buys Police Department's Web Domain 680

Posted by samzenpus
from the I-bought-the-law dept.
Brian McCrary just bought a website to complain about a $90 speeding ticket he received from the Bluff City PD — the Bluff City Police Department site. The department let its domain expire and McCrary was quick to pick it up. From the article: "Brian McCrary found the perfect venue to gripe about a $90 speeding ticket when he went to the Bluff City Police Department's website, saw that its domain name was about to expire, and bought it right out from under the city's nose. Now that McCrary is the proud owner of the site,, the Gray, Tenn., computer network designer has been using it to post links about speed cameras — like the one on US Highway 11E that caught him — and how people don't like them."

Don't be irreplaceable, if you can't be replaced, you can't be promoted.