Rick Minerich's Development Wonderland : Euler

F# Discoveries This Week 09/17/2010

RickM — Fri, 17 Sep 2010 20:25:06 GMT

ICFP approaches quickly and I’m working hard to make that those four hours of CUFP F# tutorial will be well worth your time. Meanwhile I’ve gathered the best the of the F# community for your enjoyment. Dig in!

News

September 23rd at CUFPx Michigan - Mark Harris: "A Commercial Deployment of F# "

“Mark Harris, formerly of Microsoft, currently working for Grange Insurance in Columbus, Ohio, will be presenting a case study of a commercial deployment of an F# solution. One of the highlights of this deployment--a process which took 18 hours was cut down to 6 minutes. Mark will be discussing the benefits and drawbacks of using F# in Grange's commercial app.

Audio and Video

Deep Fried Bytes Technology Podcast Episode 60: The Futures of the F# Language with Luke Hoban

“In this episode Keith and Woody sit down with F# Program Manager Luke Hoban at TechEd 2010 to discuss the futures of the F# language. Luke gave the guys the scoop on what developers can accomplish with F# and what the team has planned for upcoming releases of F# with Visual Studio.”

General

Dmitri Nesteruk 's Making DSLs in F#

“This article shows that making a DSL in F# is really simple. Of course, the thing about DSLs is they are domain-specific, so for the domain you choose you might encounter a lot more challenges. Have fun!”

Neil Carrier's Basic F# Computation Expressions Using Yield and Combine

“I decided to learn a little bit about computation expressions beyond the basic Bind/Return operations. So I made a goal of learning something about the Yield/Combine operations.”

Neil Carrier's F# Async Computation Expressions: A Tiny Model System

“Continuing my quest to learn computation expressions, I decided to explore from scratch the implementation of basic asynchronous behavior. This post is the result.”

Robert Pickering's What is object oriented programming really all about?

“People often ask me what functional programming is all about and why is it useful. In an attempt to answer this question in a way that is relevant to object oriented programmers it struck me it might be useful to look at what people find useful in modern object oriented programming.”

Celso Axelrud's Vector, Matrix and Linear Algebra in F#

“The following script snippets present the vector and matrix functionalities in Microsoft.Fsharp.Numerics namespace from Fsharp.PowerPack assemble.”

Daniel Markham's Functional TDD: Codd is my Copilot

“You work for the IRS. Your job today is to select a list of people with large bank balances so that you can do some kind of indescribably-complex tax-stuff to them. Your boss would like a list of these guys on his desk by noon.”

Vladimir Matveev's Slides And Samples

“Presentation and code samples from my recent talk on FSUG meeting.”

Stefano Ricciardi's Project Euler Problem 10 in F#

“Calculate the sum of all the primes below two million.”

Ashley Feniello's Project Euler Problem #8

“Largest products of five consecutive digits in this 1000-digit number.”

Ashley Feniello's Project Euler Problem #9

“Pythagorean triplet where a + b + c = 1000”

Ray Dacoco's TabControl in Visual F#

“TabControl is a control that can be used to organize information. It can be utilized as a good alternative to menustrip control.”

Ray Dacoco's Changing the Pointer when the mouse hovers an object

“To change the mouse pointer when the mouse hovers an object, use the Cursor property. All form controls in Visual F# has Cursor property.”

Community

StackOverflow - Does Functional Programming Replace GoF Design Patterns?

“Functional languages have plenty of best practice rules of the form "when you encounter problem X, use code that looks like Y", which is basically what a design pattern is.”

StackOverflow - F# Type declaration possible ala Haskell?

“If you want to keep readable type declarations separately from the implementation, you can use 'fsi' files (F# Signature File).”

A Look Outside

Chris Waggoner's Category Theory

“Category Theory is like Set Theory, but supposedly better. What is it, though?”

F# Discoveries This Week 08/27/2010

RickM — Sat, 28 Aug 2010 00:04:06 GMT

I’m back again with another edition of F# Discoveries this Week. The most exciting announcement this week is the new F# August 2010 CTP which brings with it the ability to build your own VS2010 F# Express Edition with Visual Studio Shell and the prospect of building F# applications on Windows Phone 7. Be sure to check out Daniel Mohl’s Windows Phone 7 template before getting started.

News and Upcoming Talks

F# (August 2010 CTP)

Announcing the F# 2.0 Standalone Tools Update

A standing invitation to F# users to "get in touch"

Don Syme lecturing at the F#unctional Londoners Meetup (9/9)

Tools and Libraries

WekaSharp: An F# wrapper for Weka (Yin Zhu)

F# and C# Win Phone List Template (Silverlight) (Daniel Mohl)

fsai Release FSharp AI library 1.10.0 (Lukáš Kouřil)

RockScroll: my new favourite Visual Studio Add-In (Kean Walmsley)

Video, Audio and Slides

Slides and samples from F# talk in Manchester (Oliver Sturm)

F# Intro Talk at NextGenUG in So’ton (Phillip Trelford)

Slides from Combinators, DSLs, HTML, and F# (Robert Pickering)

Busy .NET Developer’s Guide to F#: Basics (Ted Neward)

Technical Articles

iTunes via F# Interactive (Cameron Taggart)

F# for puzzles (Morse code decoder) (Brian McNamara)

Extracting elements from Win32 resource files (Luis Diego Fallas)

A variation on Matt Moloney's "Memento" pattern (Don Syme)

Bound Variables in F#: What Reflection Reveals (Neil Carrier)

Getting F# Running on a Continuous Integration Server (Ade Miller)

How F#'s async really works? (George Cullen)

Segment Tree in F# (Neil Carrier)

Bound Variables in F#: What Reflection Reveals (Neil Carrier)

Fuzzy Logic Experiments in F# (Neil Carrier)

Fuzzy Logic in F#, Example 1 (Neil Carrier)

Fuzzy Logic in F#, Now More Functional! (Neil Carrier)

F# “fun” with Windows Phone 7 (Fahad)

Getting started with Windows Phone in F# (Senthil Kumar)

Euler Problem 10 (Mark Pearl)

Euler Problem 16 (Mark Pearl)

Project Euler Problem 9 in F# (Stefano Ricciardi)

Project Euler Problem 8 in F# (Stefano Ricciardi)

Project Euler Problem 6 and 7 in F# (Stefano Ricciardi)

Enumerable.Skip vs Seq.skip (Mauricio Scheffer)

Getting Started and Evangelism Articles

Putting the fun in functional programming (Daniel Markham)

Back to school : Getting to know F# (Mehfuz Hossain)

Learning F# by writing C# (Alan Hemmings)

F# - sharper than C# (Josh Reuben)

Learning F# for C# developers (Bill Morrissey)

F# Community

Ars Technica - What do you think of F# ?

SO - How to merge sorted sequences in F#.

SO - Which to use, C# or F#? In this "real world" case

hubFS: F# Databse Application Samples & Articles

hubFS: MailboxProcessor.TryScan paradigm

F# Discoveries This Week 07/30/2010

RickM — Fri, 30 Jul 2010 19:03:57 GMT

It’s Friday and once again I’ve gathered up more F# content for your viewing pleasure. If you happen find yourself in the Boston area this next Monday come meet me for our New England F# User Group meeting. We are always happy to have new people interested in checking out functional programming.

News

VS2010 Keyboard Shortcuts Now Available in Letter and A4 Size

F# samples are 74% complete on langref.org (nudge nudge)

Two Contract Positions: F# Interactive in Silverlight

Scott Theleman will be speaking at New England FSUG on 8/2

Audio / Video

eXpress Persistant Objects and the F# Language

Articles

Don Syme’s Some F# Project Templates Available Online and Daniel Mohl’s An F# Silverlight MVVM Mutli-Project Template

If you have your own templates or projects-that-could-be-turned-into-templates, here are the steps to make and publish a template to the Visual Studio Gallery, making it really easy to access by the whole community.

Ben Hutchison’s Study Functional Programming or Be Ignorant

Right now, if you want to understand the state of the art in computer programming, those are your choices as I see them.

Bohdan Szymanik’s Heat/Image Mapping with .NET/F#

Most of the effort was spent aggregating and binning the data, the actual image prep was trivial. The following assumes you have an array of data to display.

Neil Carrier’s Cartesian Product of Lists in F#

So without further ado (other than to note that all the code here is presented "as-is" and without warranty or implied fitness of any kind; use at your own risk) here is my Cartesian product of lists code.

Jared Parsons’ Converting System.Func<T1..TN> to FSharpFunc<T,TResult>

Interop of delegate style types between F# and other .Net languages is a pain point that results from a fundamental difference in how delegates are represented in the F# language.

Steve Hawley’s Limit Your Memoization, Please

So the lesson in this (and in many CS problems) is that you need to really understand the specific domain of your problem before applying a sweeping technique like memoization.

Cameron Taggart’s Exploring the GAC with F# and Mono.Cecil

Mono.Cecil can be used to look inside assemblies. May be you want to search GAC to find types that implement a certain interface. In this post, I’ll show how to find all the types that implement IDisposable as an example.

Cameron Taggart’s Find Authenticode Signed Assemblies

Mono.Security can be used to check for the presence of an Authenticode signature on a assembly.

Gary Short’s XPO – F# Lists and Seqs Oh My!

Let’s assume we have a small database of people and we wish to calculate the combined age. The functional method of doing that would be to “fold” the elements of a collection of People over a function that accumulates the age of each person, in an accumulator value, which is threaded through the fold.

Mark Pearl’s F# Euler Problem 9

After some more thinking, I decided to use tuples instead and generate the permutations using the Seq.unfold method.

Maurizio Colucci’s How F# adapts to the way we think – part1

This is the first episode of a series meant to show how easily F# adapts to the way we think. I assume no knowledge of functional languages, but I do assume knowledge of an imperative language such as C#.

Wiston Gubantes’ F# Asynchronous Programming

Async programming in functional languages such as F# is such a breeze....

Community

Stack Overflow: Immutable data structures performance

Stack Overflow: Functional Reactive F# - Storing States in Games

F# Discoveries This Week 05/14/2010

RickM — Fri, 14 May 2010 21:06:49 GMT

Today, I’d like to thank all of the F# users on twitter.

Twitter’s a great place to stay up to date on the latest F# happenings and many of the posts you see here are either written by or passed on from members of this community. So, if you are interested in becoming part of the F# Twitter Community, I suggest starting with these frequent F# tweeters: @dmohl, @TigerHasse, @robertpi, @sforkmann, and @ptrelford.

I’ve also been known to occasionally tweet on F# and other programming topics. Now, on to the links.

Brian McNamara’s More F# Screencasts

My previous two screencasts (‘Getting started with F# in VS2010’ and ‘Editing F# source code in VS2010’) have been moved to MSDN, which means they’re now available in a variety of video formats. A new screencast (‘Managing F# projects in VS2010’) has also been added, so check it out!

Robert Pickering’s F# Talks in London

I’ve been in London for the past few days. I arrived Tuesday afternoon and gave at talk at “The F#unctional Londoners Meetup Group” on the Tuesday evening.

James McCaffrey’s Combinations and Permutations with F#

Understanding combinations and permutations is a fundamental skill in software testing. In this month’s Test Run column I show you how to work with combinations and permutations using code written in the new F# language.

Amanda Laucher and Josh Graham’s Pragmatic F# in Action (video)

Amanda Laucher and Josh Graham introduce the audience to F# basics showing some of its main features, emphasizing what makes it better than imperative languages.

Tomas Petricek’s ASP.NET and F# Part 1 – Creating MVC Web Applications in F#

If you want to use F# for creating an MVC application, you have a few options. It should be possible to create the web application solely as an F# project. However, we'll use a more convenient approach. We'll create a standard C# MVC project and move all the actual implementation to an F# library.

Steffen Forkmann’s FAKE – F# Make 1.20.0 Released and
Using a MailboxProcessor to speedup “FAKE – F# MAKE”

Today I released a new bugfix release for “FAKE – F# Make”. We fixed some path and logging issues and as a new feature we introduced the @@ operator which allows to combine paths.

Phillip Trelford’s Trading on IM with F#

The slides from my Trading on IM talk will be attached to this post, and the video/podcast should be appear on the Skills Matter website. I’ll also attach the 100 lines of code for shopping checkout sample, that works with a barcode scanner, I showed at the start of my presentation.

Daniel Mohl’s Integrating F# and Erlang Using OTP.NET

Recently, I ran across a post that talked about a .NET library named OTP.NET. OTP.NET is a port of a Java library named JInterface that allows a .NET application to act as an Erlang node. OTP.NET hasn't been updated in a while and the API is a bit clunky, but the provided functionality is very cool.

Nick Grattan’s Creating Web Parts with F# and
An EDSL for Emitting HTML Tables in Web Parts using F#

When writing web parts in C# for SharePoint the System.Web “table” class or “table” HTML elements are most often used for controlling layout (“div” aficionados keep your ears covered…). The code quickly gets ugly and difficult to manage – there’s no direct control to ensure correct matching of opening and closing of tags. So how about writing an EDSL that provides a syntax and constructs for doing this?

Neil Carrier’s Tiny Expert System using Monads

Below is a tiny expert system implemented using computation expressions. I managed to find a way to use the following computation expression methods: Bind, Delay, and Return.

Neil Carrier’s A Simple DSL: Tokenization to Evaluation,
S-Expressions for Semantic Networks and
A Half-Baked Scheme

This post presents a small example of the above process. It implements a small interpreter which analyzes and evaluates LISP-like prefix expressions involving integers, multiplication, and division. For example: (+ (* 1 2) (* 3 4) evaluates to a data element containing the number 14. To make clear what is happening, be sure and examine the value of tokenList before it is evaluated.

Julien Ortin’s Technical analysis indicators in F# – Bands, Signal and Ehlers

This is part of a series on technical analysis indicators in F#, based on the multi-language TA-Lib. Quick disclaimer : some of these indicators are not verified.

Yin Zhu’s F# for Project Euler Problems

Some problems have two versions of solutions, the version I first learned F# and the version based on my current knowledge of F#. The first version is usually quite easy to understand even if the reader does not know F#, while the second uses some nice F# feature or good functional programming practice in general.

Jon Harrop’s Java vs. F#

What Cliff forgot to mention is that .NET also provides value types and a far more compelling example than complex numbers is the humble hash table.

Tim Ng’s F# + WPF + Events

I recently had to do some travelling for the VS launch event in Las Vegas and QCON event in Beijing. One of the things thats nice about travelling is that it gives you time to do some things you may not otherwise do - in my case, I had a chance to try to (re) learn WPF and see how I can use F# with WPF.

Mark Needham’s Tacit Programming

I realised that this approach quite closely describes what I've been trying to drive towards in my most recent playing around with F# and it's actually quite fun trying to drive any intermediate state or storing of data in variables out of a program and just relying completely on function composition and higher order functions.

Mark Needham’s F#: My current coding approach

I spent a bit of time over the weekend coding a simple generic builder for test objects in F# and I noticed that although there were similarity with the ways I drive code in C# or Java my approach didn't seem to be exactly the same.

Ebru Cucen’s F# vs C# Samples

After my talk at ldnUG yesterday, I got nice suggestions from Zi Makki, and here is the first one: comparison between F# and C#, especially using LINQ. This subject had been quite popular once in a while, now it is probably my time to focus on this subject.

Bjorn Rochel’s Kata StringCalculator in F#

Two meetings ago we decided to do some coding on every meeting. The previous meeting we solved Kata FizzBuzz and on yesterday’s meeting we tried to dance with Roy Osheroves Kata StringCalculator.

Gunnar Peipman’s F# in ASP.NET, mathematics and testing

Starting from Visual Studio 2010 F# is full member of .NET Framework languages family. It is functional language with syntax specific to functional languages but I think it is time for us also notice and study functional languages. In this posting I will show you some examples about cool things other people have done using F#.

Luis Diego Fallas’s Defining mutually recursive classes in F#

As explained in Adventures in F#--Corecursion defining mutually recursive functions requires the use of the and keyword between function definitions. As briefly mentioned in the Type Definitions section of the manual, the and keyword can also be used in types.

Nancy Strickland’s New Features in F# 2.0 Training Video

Describes the new features in F# version 2.0, which comes included in Visual Studio 2010.

DotNetRocks in Boston (with F# Panel)

The panel suggested we add F# to our repertoire and understand its strengths, and use it where it's beneficial. I'm going to take that advice. Bottom line is if I can replace 50 lines of confusing C# code with 10 lines of elegant F#, I've done myself a service.

Rick Minerich's Development Wonderland : Euler

F# Discoveries This Week 09/17/2010

News

Audio and Video

General

Community

A Look Outside

F# Discoveries This Week 08/27/2010

News and Upcoming Talks

Tools and Libraries

WekaSharp: An F# wrapper for Weka (Yin Zhu)

F# and C# Win Phone List Template (Silverlight) (Daniel Mohl)

fsai Release FSharp AI library 1.10.0 (Lukáš Kouřil)

RockScroll: my new favourite Visual Studio Add-In (Kean Walmsley)

Video, Audio and Slides

Slides and samples from F# talk in Manchester (Oliver Sturm)

F# Intro Talk at NextGenUG in So’ton (Phillip Trelford)

Slides from Combinators, DSLs, HTML, and F# (Robert Pickering)

Busy .NET Developer’s Guide to F#: Basics (Ted Neward)

Technical Articles

iTunes via F# Interactive (Cameron Taggart)

F# for puzzles (Morse code decoder) (Brian McNamara)

Extracting elements from Win32 resource files (Luis Diego Fallas)

A variation on Matt Moloney's "Memento" pattern (Don Syme)

Bound Variables in F#: What Reflection Reveals (Neil Carrier)

Getting F# Running on a Continuous Integration Server (Ade Miller)

How F#'s async really works? (George Cullen)

Segment Tree in F# (Neil Carrier)

Bound Variables in F#: What Reflection Reveals (Neil Carrier)

Fuzzy Logic Experiments in F# (Neil Carrier)

Fuzzy Logic in F#, Example 1 (Neil Carrier)

Fuzzy Logic in F#, Now More Functional! (Neil Carrier)

F# “fun” with Windows Phone 7 (Fahad)

Getting started with Windows Phone in F# (Senthil Kumar)

Euler Problem 10 (Mark Pearl)

Euler Problem 16 (Mark Pearl)

Project Euler Problem 9 in F# (Stefano Ricciardi)

Project Euler Problem 8 in F# (Stefano Ricciardi)

Project Euler Problem 6 and 7 in F# (Stefano Ricciardi)

Enumerable.Skip vs Seq.skip (Mauricio Scheffer)

Getting Started and Evangelism Articles

Putting the fun in functional programming (Daniel Markham)

Back to school : Getting to know F# (Mehfuz Hossain)

Learning F# by writing C# (Alan Hemmings)

F# - sharper than C# (Josh Reuben)

Learning F# for C# developers (Bill Morrissey)

F# Community

F# Discoveries This Week 07/30/2010

News

F# samples are 74% complete on langref.org (nudge nudge)

Audio / Video

Articles

Don Syme’s Some F# Project Templates Available Online and Daniel Mohl’s An F# Silverlight MVVM Mutli-Project Template

Community

F# Discoveries This Week 05/14/2010

Steffen Forkmann’s FAKE – F# Make 1.20.0 Released and Using a MailboxProcessor to speedup “FAKE – F# MAKE”

Nick Grattan’s Creating Web Parts with F# and An EDSL for Emitting HTML Tables in Web Parts using F#

Neil Carrier’s A Simple DSL: Tokenization to Evaluation, S-Expressions for Semantic Networks and A Half-Baked Scheme

Julien Ortin’s Technical analysis indicators in F# – Bands, Signal and Ehlers

Steffen Forkmann’s FAKE – F# Make 1.20.0 Released and
Using a MailboxProcessor to speedup “FAKE – F# MAKE”

Nick Grattan’s Creating Web Parts with F# and
An EDSL for Emitting HTML Tables in Web Parts using F#

Neil Carrier’s A Simple DSL: Tokenization to Evaluation,
S-Expressions for Semantic Networks and
A Half-Baked Scheme