January 2012
2 posts
Simian - SIMIlarity ANalyzer →
Simian (Similarity Analyser) identifies duplication in Java, C#, C, C++, COBOL, Ruby, JSP, ASP, HTML, XML, Visual Basic, Groovy source code and even plain text files. In fact, simian can be used on any human readable files such as ini files, deployment descriptors, you name it.
Codebook →
November 2011
7 posts
Small Business 401k →
I need to set-up a new 401k for my new consulting job. Looking into going through Vanguard directly. E-mail me if you have better suggestions.
[Sermon] Wise Thinking →
I am currently reading Eat This Book by Eugene Peterson. My coworker Matt Moran mentioned he has been listening and reading Jeff Vanderstildt’s stuff lately, and I have never heard of Jeff. Matt gave me this link to check out.
Gospel Fluent Thinking →
I am currently reading Eat This Book by Eugene Peterson. My coworker Matt Moran mentioned he has been listening and reading Jeff Vanderstildt’s stuff lately, and I have never heard of Jeff. Matt gave me this link to check out.
A Note on F# Quotations →
The author, Yin Zhu, works on the F# Optimization Domain Specific Language.
[Survey] Truthy Maintenance by David McAllester →
Usenix 08: Optimizing TCP Receive Performance →
The performance of receive side TCP processing has traditionally been dominated by the cost of the ‘per-byte’ operations, such as data copying and checksumming. We show that architectural trends in modern processors, in particular aggressive prefetching, have resulted in a fun- damental shift in the relative overheads of per-byte and per-packet operations in TCP receive processing, making...
Nagle’s Algorithm is Not Friendly towards Small... →
Title is a bit of flame bait. The author’s real point is that it is not friendly toward small requests if the receiver is using Delayed ACKs.
October 2011
5 posts
Good Error Messages research
Bastian Heeren’s Ph.D. thesis Top Quality Type Error Messages
Bastian Heeren’s IFL 2006 Heuristics for type error discovery and recovery
A Type Error Slicer for SML
…add more later.
Arjen Langebaerd. Repair Systems - Automatic Correction of Type Errors in Functional Programs [pdf]
…add more later.
PostSharp - .NET AOP library →
Was trying to think of the name of this library recently. Searched my twitter feed and found it. Posting it here for redundancy. Shame it is advertised as AOP library, since it works so well for other purposes.
Stack Overflow - Library of Useful (Difficult) SQL... →
Why is writing SQL difficult?
The tongue-in-cheek answer is that most people don’t care how hard writing SQL is. It keeps people employed, and the next milestone in automation is a lot of R&D with scary consequences for most enterprise IT professionals.
But here is an engineering answer:
It seems to me that in SQL, one of my favorite questions becomes particularly important: what optimizations are optional and what...
Famous Russian CS Professor W.E. Wolfengagen's CAM...
Will watch later.
This is W.E. Wolfengangen’s lectures on the Categorical Abstract Machine. Describes a method for evaluation of programs when the access to computational environment is modeled as a composition of projections.
Can’t seem to find lectures 5-8?
Categorical Abstract Machine. Lecture 1 of 8: Computation in a Category
Topics: The notion of Categorical Abstract...
September 2011
3 posts
The Top 20 Applications for an... Infinitely Fast... →
The Nonlinear Curve Fitter (NLFit) →
Gmail recommended this to me when I opened up a thread on the FONC mailing list about control theory and typed the word “nonlinear”. Seems very interesting.
“Abstract
I’ll give a historical survey of Kahn networks and their...”
– Kahn Networks At The Dawn Of Functional Programming
David MacQueen
August 2011
18 posts
Types for Dyadic Interaction →
We formulate a typed formalism for concurrency where types denote freely composable structure of dyadic interaction in the symmetric scheme. The resulting calculus is a typed reconstruction of name passing process calculi. Systems with both the explicit and implicit typing disciplines, where types form a simple hierarchy of types, are presented, which are proved to be in accordance with...
The Strange Loop conference videos →
[LtU] Question About Computational Complexity →
Type Systems For Polynomial-time Computation
This thesis introduces and studies a typed lambda calculus with higher-order primitive recursion over inductive datatypes which has the property that all definable number-theoretic functions are polynomial time computable. This is achieved by imposing type-theoretic restrictions on the way results of recursive calls can be used.
The main technical...
ProGuard Obfuscation FAQ →
An Introduction to Functional Programming Through... →
I had never heard of this book before, but seeing as how it was just reprinted, there must be a large audience for its writing style.
INF: Frequently Asked Questions - SQL Server 2000... →
I was asked a good interview question awhile back, about the different ways to define a temporary table. To be honest, I thought I nailed my answer, but the interviewer corrected me. A few weeks later, I tested his corrections to see if they were true, and they were not. That said, I never got to the bottom of the exact differences between table variables and temp tables, until now.
Learning...
Indy.Sockets →
I’ve been thinking about writing a SFTP library for .NET for fun. Started by looking at what socket abstractions there are. I really know absolutely nothing about SFTP from a low-level viewpoint, so I am probably starting in the wrong spot. If you have suggestions to help this hobby project along, email me or send me a message via twitter.
3 tags
[LtU] The essence of Dataflow Programming by Tarmo... →
Interesting, good paper. However, one major gripe. They write in one section:
Analogously to causal stream functions, one might also consider anticausal stream functions, i.e., functions for which the present value of the output signal only depends on the present and future values of the input signal. […] However, in real life, causality is much more relevant than anticausality!
You...
1 tag
Functionally Modeled User Interfaces →
Abstract. Fruit is a new user interface toolkit based on a formal model of user interfaces. This formal basis enables us to write simple, concise executable specifications of interactive applications. This paper presents the Fruit model and several example specifications. We consider one example (a basic media controller) in detail, and contrast the executable specification style of Fruit with a...
1 tag
Antony Courtney on the success (and failure) of... →
[Haskell-cafe] Re: Why binding to existing widget toolkits doesn’t make any sense
Hi Conal (and Paul and Henrik and everyone else!),
Apologies for the delay in replying. Paul is quite right about my day
job keeping me quite busy, although I've been enjoying watching the
discussion.
I think there are several reasons that Fruit never really caught on.
First and foremost, Fruit never...
1 tag
Erbium: A Deterministic, Concurrent Intermediate... →
Tuning applications for multi-core systems involve subtle concepts and target-dependent opti-mizations. New languages are being designed to express concurrency and locality without reference to a particular architecture. But compiling such abstractions into efficient code requires a portable, intermediate representation: this is essential for modular composition (separate compilation), for...
4 tags
Peta-Scale I/O with the Lustre File System →
The Lustre™ file system first went into production in Spring 2003 on the Multiprogrammatic Capability Resource (MCR) cluster at Lawrence Livermore National Laboratory (LLNL). The MCR cluster was one of the largest clusters at that time with 1100 Linux compute nodes as Lustre clients. Since then, the Lustre file system has been deployed on larger systems, notably the Sandia Red Storm deployment,...
The Agorics papers →
K. Eric Drexler and Mark S. Miller’s original papers on Agorics.
How The Pursuit Of "Light Speed" Broke Equity... →
Argues that markets now operate at such high speeds for bid and offer that the National Best Bid Or Offer (NBBO) is totally irrelevant. The implication is that if that is true, then traditional market mechanisms are essentially being subverted and normal regulatory rules don’t apply. Interesting.
Step Right Up: It's HFT Whack-A-Mole Time →
An algorithmic trading algorithm was causing its own oscillation! Very interesting.
What is state? [Machine Learning (Theory) blog] →
Includes some good comments by readers, including Andrej Bauer.
2 tags
Information and Control: Witsenhausen Revisited →
What did Witsenhausen’s counterexample really prove about information and control?
The role of information in the context of control is a deep issue. To get at this, we review Witsenhansen’s notions of information patterns for control problems. While staying in that basic framework, we then use ideas from traditional information theory as we re-examine Witsenhausen’s famous...
Log Buffer: #104: a Carnival of the Vanities for... →
Fabulous rant.
July 2011
5 posts
Nick Bickford's cellular automata and mathematics... →
Overview of Stanford University's CS Curriculum in... →
Mindblowing.
Vertica Under the Hood: The Query Optimizer →
This is fairly interesting technical stuff for “marketing material”. A good jumping off point for learning about Vertica’s design.
z is for Zeitgeist →
A language designer’s thoughts on hypermedia’s ability to influence language design:
I have always been fascinated by videogames, not so much for their narrative or competitive elements, but for the way they let you discover mysterious alternative worlds that operated according to their own rules. In a way both hypermedia and multimedia can be seen as subsets of gameworlds:...
Proving Correctness via Free Theorems: The Case of... →
Free theorems feature prominently in the field of program transformation for pure functional languages such as Haskell. However, somewhat disappointingly, the semantic properties of so based transformations are often established only very superficially. This paper is intended as a case study showing how to use the existing theoretical foundations and formal methods for improving the situation....
June 2011
23 posts
Do I need Dropline Gnome? [July 2006] →
…and Dropline replaces the shadow package with… shadow. (OMG!) …and let’s clarify something—it’s not “Slack developers”, it’s “Patrick Volkerding” who is one guy. Another thing you’re managing to omit is why Slackware doesn’t use PAM. Patrick has been pretty clear about this in the distant past (because answering...
default iptables [May 2005] →
On the other hand, by default there are no services listening on the network interface - there are some listening on loopback but they can only be reached from the machine itself.Actually, loopback services can be bounced attack from the local subnet, if you’re very careful. But defending against this is somewhat complicated, and the attack is complicated itself. It’s not worth...
Re: mod_auth_pam [Jan 2001] →
»»> “Ben” == Ben Collins <bcollins@debian.org> writes: » shadow sucks. I use Kerberos or LDAP whenever I can. Both » protocols lend themselves much better to PAM-integration, btw. Ben> That’s the most ignorant statement I have seen in awhile. So I agree. The implication (admittedly it may have been taken out of context, I don’t...
PowerShell script to change PST location →
This handy PowerShell script allows us to map everyone’s PST location to our file server. This is extremely useful, considering Office 2010 auto-archives everything by default and you have to manually uncheck things you don’t want archived.
Broader question: Why aren’t we using Google instead of Microsoft? :( [Not that Google is without sin, there are tons of design flaws in...
NetworkedHelpDesk's Ticket Sharing API: A Glimpse... →
Collaboration in the enterprise software space has been plagued with process and technology challenges. The advent of lightweight open API specifications from industry associations such as NetworkedHelpDesk alleviate some of these technical challenges and are being touted as examples of what future enterprise APIs will resemble.
I haven’t read this yet, but if people are truly...
Add Spelling and Grammar Checking to Any Online... →
After the Deadline is a free REST based service that provides Spelling, Style, and Grammar checking support to any application that has Internet access. For personal use developers may use the free online server hosted by After the Deadline. Commercial users need to host their own server, the software for which is being offered under the GNU General Public License.
Daniel Jackson's 6.005 lecture on "How to Design... →
There is a lot of good content in these slides, summarized towards the end with very pragmatic advice.
Pure Type Systems for Functional Programming →
We present a functional programming language based on Pure Type Systems (PTSs). We show how we can define such a language by extending the PTS framework with algebraic data types, case expressions and definitions. To be able to experiment with our language we present an implementation of a type checker and an interpreter for our language.
PTSs are well suited as a basis for a functional...
What’s Special About Identity Types →
From a homotopy theorist’s point of view, identity types and their connection to homotopy theory are perfectly natural: they are “path objects” in the category of types. However, from a type theorist’s point of view, they are somewhat more mysterious. In particular, identity types are just one particular inductive family; so what’s special about them that they give us homotopy theory and...
Dissecting the Disruptor: What's so special about... →
The difference between the ring buffer as we’ve implemented it, and the queues we had traditionally been using, is that we don’t consume the items in the buffer - they stay there until they get over-written. Which is why we don’t need the “end” pointer you see in the Wikipedia version. Deciding whether it’s OK to wrap or not is managed outside of the...