As part of the London Green Hackathon I created the AMEE-in-Excel addin to tightly integrate this data and calculations into Excel.

So, if Excel is your preferred way to work with climate data, then this should be in your toolkit.

All code is open source and hosted at . Pull-requests are welcome!

UPDATE
Hurrah! AMEE in Excel won the behaviour change prize:

We believe over 80% of the sustainability field currently use spreadsheets. As a process, this is broken, not scalable and inaccurate. AMEE in Excel Integrates spreadsheets with web-services, to create a behaviour change that could address this issue and bring more credibility to the market.

So, if you want to collaborate on some Award Winning Software , send in those pull requests

My session was a hands on introduction to functional programming techniques with code samples in Javascript and F#. The focus on the session was to get peopling thinking about first class functions; and the techniques they enable to simplify and increase readability of code when solving certain classes of problems.

The code samples can be found at:

• Javascript – https://github.com/mrdavidlaing/functional-javascript
• F# – https://github.com/mrdavidlaing/functional-fsharp

An online/executable version of the Javascript code is at http://functional-javascript.davidlaing.com.

Judging by the feedback I received, the session went very well. People seemed to like the hands-on format of the session; and just being left alone for a while to learn something at their own pace.

A refactoring I use frequently to deal with this is Replace Conditional with Polymorphism; but for simple switches, its always seemed like a rather large hammer.

Take the following simple example that performs slightly different processing logic based on the credit card type:

Its highly likely that the number of credit card types will increase; and that the complexity of processing logic for each will also increase over time. The traditional application of the Replace Conditional with Polymorphism refactoring gives the following:

This explosion of classes containing almost zero logic has always bothered me as quite a lot of boilerplate overhead for a relatively small reduction in complexity.

Consider however, the functional approach to the same refactoring:

Here we have obtained the same simplification of the switch statement; but avoided the explosion of simple classes. Whilst strictly speaking we are still violating the Open Closed Principle; we do have a collection of simple methods that are easy to comprehend and test. It’s worth noting that when our logic becomes very complex; converting to the OO Strategy pattern becomes a more compelling option. Consider the case when we include a collection of validation logic for each credit card:

In this case the whole file starts to feel too complex to me; and having the logic partitioned into separate strategy classes / files seems more maintainable to me.

To conclude then, the fact that languages treat functions as first class constructs, gives us the flexibility to use them in a “polymorphic” way; where our “interface” is the function signature.

And for some problems, like a refactoring a simple switch statement; I feel this gives us a more elegant solution.

Interestingly, Javascript seems to have more functional than object orientated characteristics; so it seems reasonable to learn it wearing my functional hat.

I’ve been enjoying learning Ruby syntax via RubyKoans – little tests that teach you syntax and convention as you make them pass

I though I’d create a similar set of Functional Javascript Koans to help refresh my Javascript skills.

Its a bit rough; so please fork and contibute back improvements.
https://github.com/mrdavidlaing/javascript-koans

Getting FlexMojos 3.6.1 working with Flex 4, running Flash Builder 4′s version of unit tests and FlexMonkey4′s version of acceptance/UI tests is pretty tricky.

Hopefully this sample project – http://github.com/mrdavidlaing/flexmojos-sample along with this screencast will save someone else the pain I went through to get all these playing together.

Howto add new component to FlexITP from David Laing on Vimeo.

Patches welcome – just clone the git repo make your change, and request a pull.


dpkg-reconfigure mysql-server-5.0


Hopefully that will save someone some hair pulling

If you’re about to name a class **Util; think harder – there is a better name that discribes what that class is for:
Chriss Missal has some advice for you

Faced with the prospect of heaps of left hand side => right hand side code in your DTO of anti-corruption layer? Consider Jimmy Bogard’s Automapper

Very useful when you need to write data manipulation scripts for production databases.

BEGIN TRY

    BEGIN TRAN

        --Some SQL

    COMMIT TRAN

END TRY
-- Catch the errors on the inserts
BEGIN CATCH

    ROLLBACK TRAN
    SELECT ERROR_MESSAGE()

END CATCH

For example, consider the following function:

      string StringReplace(string haystack, string needle)

If this function is side-effect free, we can use it without fear like this:

        string menagerie = "cat,dog,bee,llama";
        string catFreeMenagerie = StringReplace(menagerie, "cat");
        string beeFreeMengerie = StringReplace(menagerie, "eric");

        Assert.AreEqual(",dog,fish,llama", catFreeMenagerie);
        Assert.AreEqual("cat,dog,,llama", beeFreeMengerie);

However, if StringReplace() had the side effect of also changing the passed in haystack, then the second Assert would fail, because the first StringReplace has the unexpected side effect of changing one of its arguments.

Evans in the DDD book has quite a bit to say about this; arguing that having side effect free functions goes a long way towards making a supple design

Side effect free functions also make testing & refactoring easier (less state to worry about etc)

Remember, a function that changes its parameters is rude, and should not be trusted!

PS: Eric the half a bee lyrics

The test was to check whether some tracking tag javascript was being inserted into the page correctly or not.

I assumed that I could get the page source as it was being delivered to the browser by calling selenium.GetHtmlSource(); and then check that for the javascript string I was expected.

Unfortunately, GetHtmlSource is just a proxy for the browsers DOM.InnerHTML method; and that returns the Html after it has been preprocessed by the browser.

Turns out that preprocessing does a couple of funky things, including

• Changing line-endings (Firefox)
• Changing capitalization (IE6)
• Seemingly random removal / insertion of ” & ‘  (IE6)

So, when I was expecting a string like this:

<!--
   var amPid = '206'';
   var amPPid = '4803';
   if (document.location.protocol=='https:')
...[snip]...

IE6 was presenting me with:

<!--
   var amPid = '206'';
   var amPPid = '4803';
   if (document.location.protocol=='https:')
...[snip]...

A possible solution is to ignore case, whitespace and quotes when doing the comparison, with a helper method like this:

///

        /// Use this to compare strings to those returned from selenium.GetHtmlSource for an Internet Explore instance
        /// (IE6 seems to change case and inclusion of quotes, especially for Javascript.?)
        /// 

        ///
        ///
        private static void AssertStringContainsIgnoreCaseWhiteSpaceAndQuotes(string expected, string actual)
        {
            string expectedClean = Regex.Replace(expected, @"s", "").ToLower().Replace(""","").Replace("'","");
            string actualClean = Regex.Replace(actual, @"s", "").ToLower().Replace(""", "").Replace("'", "");
            StringAssert.Contains(expectedClean,actualClean,
                                  string.Format("Expected string nn{0} nnis not contained within nn{1}", expected, actual));
        }

It was the line endings that really floored me; because they were automatically normalized/corrected by my test runner when displaying the error. Aaargh!