Is this a known pattern?
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
I don't know if it's known or not. You could call it "Query Mapper"
If your actions inspire others to dream more, learn more, do more and become more, you are a leader." - John Quincy Adams
You must accept one of two basic premises: Either we are alone in the universe, or we are not alone in the universe. And either way, the implications are staggering” - Wernher von Braun -
Nicholas Butler wrote:
I just called it caching
Most people do. First law of patterns. They are a fancy name for stuff you already do.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
"Mind bleach! Send me mind bleach!" - Nagy Vilmos
My blog | My articles | MoXAML PowerToys | Mole 2010 - debugging made easier - my favourite utility
Pete O'Hanlon wrote:
First law of patterns. They are a fancy name for stuff you already do.
Along with the first law of programming ( "it's already been done" ), I was hoping someone had already come up with the fancy name. Nick
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
YAPNBUDP - Yet another pretentiously named but unnecessary design pattern :)
"If you think it's expensive to hire a professional to do the job, wait until you hire an amateur." Red Adair. nils illegitimus carborundum me, me, me
-
As an alternative, it also looks a bit like a Query Object - mapping onto a Repository pattern.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
"Mind bleach! Send me mind bleach!" - Nagy Vilmos
My blog | My articles | MoXAML PowerToys | Mole 2010 - debugging made easier - my favourite utility
There you have it: QORP!
-
peterchen wrote:
It's known as PNAMUT - Pretentious Name for Muddling Through.
Correct, but not very catchy :)
peterchen wrote:
The purpose of the data layer method (as you call it) is to protect the application against changes; e.g. a new privacy regulation mandates you may not track age, only states such as "above minimum drinking age".
That was a contrived example but I agree: it's certainly not High Church. Nick
When you pronounce it quickly, you can make it sound almost like "PEANUT".
FILETIME to time_t
| FoldWithUs! | sighist | WhoIncludes - Analyzing C++ include file hierarchy -
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
I use this stuff all the time, and love it !! Linq, Lamdas, Linq with Lamdas.. It saves a lot of time with EF.
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
'Specification Pattern' with only one logical chain.
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
Isn't it just a simple Facade pattern?
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
I have been working with a pattern called "composite specification" that uses lambda expressions in this way. We are looking at combining it's use with NHibernate, which can turn the composed lambdas into SQL. Seems like a pretty powerful, flexible approach to me.
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
How about LOOP? LINQ-Object Oriented Programming
"To alcohol! The cause of, and solution to, all of life's problems" - Homer Simpson
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
when you use lambda expression and delegates, these are a variant of the observer pattern.
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
-
I use this stuff all the time, and love it !! Linq, Lamdas, Linq with Lamdas.. It saves a lot of time with EF.
Baxter R Pearson wrote:
It saves a lot of time with EF.
Exactly :) I've sent you a PM - could you let me know if it doesn't come through ( sometimes they go missing. ) Nick
-
Isn't it just a simple Facade pattern?
Nathan Gloyn wrote:
Isn't it just a simple Facade pattern?
It does hide a lot of complexity, but I think the difference is that the parameters passed are functions not values. I don't know if that makes it a different pattern, though :) Nick
-
Nathan Gloyn wrote:
Isn't it just a simple Facade pattern?
It does hide a lot of complexity, but I think the difference is that the parameters passed are functions not values. I don't know if that makes it a different pattern, though :) Nick
From the all knowing Wikipedia: A facade is an object that provides a simplified interface to a larger body of code, such as a class library. A facade can: - make a software library easier to use, understand and test, since the facade has convenient methods for common tasks; - make the library more readable, for the same reason; Certainly sounds like its a facade based on that definition :)
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
Technically it's a DSL (Domain Specific Language) implemented on top of a formal language. You can tell if it's a DSL if simply reading the words makes approximate sense in English: User fetch all where the user age is greater than 21. You could obviously improve it: Fetch all users where the user age is greater than 21.
var users = Fetch.All.Users( where: user => user.Age > 21 );
The paradigm you are using is very close to a fluent interface - technically fluent interfaces need to happen with method calls (
DAL.Users().Where().Age().GreaterThan(21)) but there isn't any reason you can't violate that - especially if it increases clarity (which yours does).He who asks a question is a fool for five minutes. He who does not ask a question remains a fool forever. [Chineese Proverb] Jonathan C Dickinson (C# Software Engineer)
-
I have been working with a pattern called "composite specification" that uses lambda expressions in this way. We are looking at combining it's use with NHibernate, which can turn the composed lambdas into SQL. Seems like a pretty powerful, flexible approach to me.
I've sent you a PM - could let me know if it goes missing? ( they sometimes do ) Nick
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick
-
I'm having difficulty finding a name for a style of programming. You can make one up if you like, but I'd prefer something that is already documented :) I've written a layer over the Entity Framework that allows the application code to pass parameters into the data layer that shape the returned result sets. So you can write something like this:
List users = DAL.User.FetchAll( where: user => user.Age > 21 );
It's declarative programming, but I was looking for a more specific name. Something like "locality of intent". Basically, you say what you need in the place where you need it. It's the opposite of having a data layer method like this:
List FetchAllUsersWhereAgeGreaterThan( int minimumAge )
Is this a known pattern? I've run out of obvious words to Google. Ta, Nick