technology from back to front

Archive for October, 2006

Retail Systems Awards

LShift and Habitat partnership reaches the final judging stages of the Retail Systems Awards 2006.

As a result of their work on the Habitat Gift Service, LShift and Habitat have reached the final judging stage in the Retail Systems Awards giftcard/loyalty programme of the year category. The award recognises the retailer and agency who can demonstrate use of technology to drive improvements in customer relationship management.

The primary criteria for judging are the delivery of definable and significant business benefits, innovation and originality of application, ROI and project management issues such as delivery on time and within budget.

LShift and Habitat will both attend the awards presentation at The Grosvenor House Hotel, London on Tuesday November 14. The announcement of the winners will be made on the night.


LShift and BIMA Awards

The Yahoo! House Price Centre has been shortlisted for an BIMA (British Interactive Media Association) award in the B2C category.

The Yahoo! House Price Centre is a free service from Yahoo! UK and Ireland that allows you to discover the price paid for residential property sold in England and Wales right back to April 2000, and in Scotland back to June 2003. This information is drawn from the publicly accessible Land Registries that record this information on behalf of the government. The site was built by LShift in partnership with Poke.


Smalltalk UK meetings, 20-21 Oct

This last weekend saw two Smalltalk-related events: the second Smalltalk UK meeting, and a Camp Smalltalk, both held at JP Morgan’s offices in London.

On the Saturday, Bryce Kampjes gave an in-depth guided tour of his Exupery compiler (see also SqueakSource), and Francisco Garau gave an overview of the now ten-year-old, massively complex JP Morgan Smalltalk project, Kapital (which Cincom are very pleased by).

Friday’s meeting saw two presentations. The first, by John Aspinall, author of ReStore (warning: extremely obnoxious use of blink tag), an object-relational mapping for Smalltalk, covered the basics of the ReStore system. The second, by Andy Bower of Object Arts (who build Dolphin Smalltalk), introduced his Smalltalk trading platform, Alchemetrics, and demonstrated its use for developing and testing automated trading strategies.

Both talks were fascinating, particularly Andy’s presentation of the details of developing and using an automated trading system for working with Real Money in Real Markets (scary!), but there was one interesting technical point from John’s talk I wanted to draw particular attention to here.

One very clever part of ReStore’s design is the way it converts ordinary Smalltalk code into efficient SQL queries. An object somewhere between a null object and an interpreter (in the form of a partial-evaluator) acts as a proxy for the complete collection being selected from. Most messages sent to this proxy are handled by its doesNotUnderstand handler. Each such message causes it to build another stage of the SQL query it represents. Once the query block has finished executing on the proxy object, the proxy is asked to convert itself into a finished SQL query ready for execution. (This is extremely similar to the approach taken to collection iteration in Higher-Order Messaging.)

For example,

allPersons := aReStore instancesOf: Person.
"Retrieve all instances of Person with the surname Smith"
allPersons select: [ :each | each surname = 'Smith'].

will be transformed into


through the magic of Smalltalk’s reflective ability. The ReStore developer’s manual has more examples.




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