Translating intentions and mechanisms

re: Translating intentions and mechanisms

KAE — Tue, 25 Mar 2008 21:53:40 GMT

>AttemptMultiple(()=>Execute());

Why not "AttemptMultiple(Execute);" ?

re: Translating intentions and mechanisms

Eric Lippert — Tue, 25 Mar 2008 21:55:48 GMT

That would work in this case. But what if the code inside the macro took an argument?

re: Translating intentions and mechanisms

Matthew Douglass-Riley — Wed, 26 Mar 2008 01:21:53 GMT

Relevant to the "automatic retry" discussion:

http://blogs.msdn.com/oldnewthing/archive/2005/11/07/489807.aspx

re: Translating intentions and mechanisms

Bob Denny — Wed, 26 Mar 2008 04:10:04 GMT

In my case, it's dealing with atronomical instruments that occasionally misbehave in an automated image acquisition system. The devices operate below a standardized driver layer. And the real problem is political - users want me to do automatic retries instead of them having to fix the problem (or have their instrument supplier fix it!). It's very difficult to explain why I refuse to put in "recovery" code for their flaky device. It needs to be in the driver if anywhere, and I say "nowhere"; talk to the people to whom you paid money for the instrument. Tell them to make it work reliably.

Anyway, the reasons for avoiding retries are (1) avoiding damage to equipment, and (2) avoiding bloating my software with device-dependent code, and simultaneously defeating the whole purpose of drivers. "No software victories over hardware!"

re: Translating intentions and mechanisms

Christopher Bennage — Wed, 26 Mar 2008 07:21:20 GMT

Great post, Eric. Keepem' coming.

re: Translating intentions and mechanisms

Olmo — Wed, 26 Mar 2008 11:38:05 GMT

The whole standard SQL synthax looks like an example of the third case (too much emphasis in intention). I think the Linq synthax is better, not only for allowing intellisense but for expressing the mechanism (order) the operations should be done.

When will we have a Microsoft Linq Server that takes ExpressionTrees insead of plain SQL :P

re: Translating intentions and mechanisms

RichB — Thu, 27 Mar 2008 16:39:52 GMT

Deadlocks is about the only area I've come across where this technique is useful.

re: Translating intentions and mechanisms

Merit — Sat, 29 Mar 2008 00:37:30 GMT

I imagine everyone here already knows about it but www.TheDailyWTF.com is chock FULL of examples of mismatches between intentions and mechanisms.

re: Translating intentions and mechanisms

WaterBreath — Sat, 29 Mar 2008 08:03:38 GMT

>> Why not "AttemptMultiple(Execute);"

> That would work in this case. But what if the code inside the macro took an argument?

There is a subtle lesson to be learned here about crafting examples, and possibly also about the illuminating aspect of teaching the general solution as opposed to the specific solution... Thank you Eric, for an unexpected epiphany. =)

Community Convergence XLII

Charlie Calvert's Community Blog — Mon, 31 Mar 2008 03:45:04 GMT

LINQ in Portuguese ( Direct ) http://www.linqpad.net Eric Lippert Why Can't I Access A Protected Member

Community Convergence XLII

Charlie Calvert's Community Blog — Mon, 31 Mar 2008 07:56:31 GMT

Welcome to the forty-second issue of Community Convergence. The last few weeks have been a busy time

re: Translating intentions and mechanisms

Luc De Wilde — Thu, 17 Apr 2008 22:56:15 GMT

Hey Eric (and the others), I' m a Belgian banker who programs for fun (over ten years ago I did this for my job). i surely agree with the translating manner, but I have some doubt with the statement: "Tell the user that something failed and let them decide when and if to retry it." I explain: on my home-network we have now and then some transmission problems. I have written a small program to make a website with photos en I have to transfer this websites to my webspace. The transfer of a website takes in certain cases an hour or more, so I want my computer to upload the website unattended .... but I did NOT find a (free) FTP-program that I could tell to retry for about a minute or two when something goes wrong (they all have read your statement?). So I have written a simple FTP-program myself with the AttemptMultiple-approach ... and it works fine! (Sorry for the errors in my writing English, my mother-language is Dutch.)