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Linq is all about defining the query instead of the execution of the query. You say you can implement Except in a single line of code. Can you also do that for grouping, ordering, projection? And all those other possibilities, all used in combination?
Using Ling you are sacrificing a little performance, and you are (read: should be) gaining a lot in maintenance. You can implement the above probably without problems. Can you also read the implementation of others without any problems? Using Linq you and your co-workers are all using the same methods, and therefor, can read each others code a lot easier, compared to a different implementation for you and every co-worker you have.
Of course, you can completely kill the performance, and no-one will say that Linq is faster, and yes, you have to know what you are doing. But that is no different from all the 'other tools in your toolbox'.
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Linq => Backward SQL
We're philosophical about power outages here. A.C. come, A.C. go.
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Actually, I think of it as SQL the right way round.
A good clue comes from intellisense. It cannot get the field names unless you write the FROM before the SELECT.
"If you don't fail at least 90 percent of the time, you're not aiming high enough."
Alan Kay.
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I use whatever is appropriate, and refuse to use new language features just because they're new. I still resist using Entity Framework because generalization on that scale usually means bloated and inefficient code.
".45 ACP - because shooting twice is just silly" - JSOP, 2010
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You can never have too much ammo - unless you're swimming, or on fire. - JSOP, 2010
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When you pry the gun from my cold dead hands, be careful - the barrel will be very hot. - JSOP, 2013
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Well, no, Harold, I haven't seen that style because I haven't read any buggy code that was written by someone who did not know that the 'ForEach sequence iterator only works on a List<T>, and will fail on an IEnumerable<WhatEver> ... until ... now 
Eric Lippert would agree with you, however, that the 'ForEach iterator is 'gang aft agley': [^]. As Eric (famously) said: "Remember, the purpose of code is not just to communicate to the compiler it is to communicate to the future reader of the code; make it as clear as possible."
While I do think there's something that many programmers innately find "satisfying" psychologically about method chaining a la functional programming, perhaps there is also an attraction to writing the most recent syntax as a way to ... "be cool" ?
But, wait a minute, what about when the purpose of the 'ForEach iterator is to operate on a "projected" IEnumerable to modify elements of a collection where attempting to modify those elements in standard 'for, 'foreach, loops would result in an error. In that case, perhaps the creation of an "extra" List in order to use 'ForEach is ... useful ?
cheers, Bill
«There is a spectrum, from "clearly desirable behaviour," to "possibly dodgy behavior that still makes some sense," to "clearly undesirable behavior." We try to make the latter into warnings or, better, errors. But stuff that is in the middle category you don’t want to restrict unless there is a clear way to work around it.» Eric Lippert, May 14, 2008
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BillWoodruff wrote: Well, no, Harold, I haven't seen that style because I haven't read any buggy code that was written by someone who did not know that the 'ForEach sequence iterator only works on a List<T>, and will fail on an IEnumerable<WhatEver> ... until ... now
Damn 
Can I get away with this if I pretend it's my own extension method?
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Hi, Harold, I am sending you via mental telepathy one of my rationalization-rations; I don't know why the gods give me so many ... is it because it's so clear I need them ?
cheers, Bill
«There is a spectrum, from "clearly desirable behaviour," to "possibly dodgy behavior that still makes some sense," to "clearly undesirable behavior." We try to make the latter into warnings or, better, errors. But stuff that is in the middle category you don’t want to restrict unless there is a clear way to work around it.» Eric Lippert, May 14, 2008
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BillWoodruff wrote: and will fail on an IEnumerable<WhatEver>
Which is why I have an extension method to overcome that shortcoming. 
Marc
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Marc Clifton wrote: Which is why I have an extension method to overcome that shortcoming
You and Eric:
Eric Lippert, 2009, op. cit. "A number of people have asked me why there is no Microsoft-provided “ForEach” sequence operator extension method. The List<t> class has such a method already of course, but there’s no reason why such a method could not be created as an extension method for all sequences. It’s practically a one-liner:"
public static void ForEach<T>(this IEnumerable<T> sequence, Action<T> action)
{
foreach(T item in sequence) action(item);
}For me, seems like something happened this year where suddenly I felt more comfortable (secure ?) using Linq goodness, and Yield Return, and IEnumerables of whatever, and writing extension methods that have a "socket" for an Action, or Func. I have seen some students bounce off those semantics/facilities, and some take to it like the proverbial "ducks to water."
And (I hope you can still blush), you were an influence on me to "get more into" the method-chaining style, which I really like, now.
Not that I am "catching up" with you (technically) in any way, though: occasionally I get a glimpse of your shadow going around a corner 
thanks for the mentories, Bill
«There is a spectrum, from "clearly desirable behaviour," to "possibly dodgy behavior that still makes some sense," to "clearly undesirable behavior." We try to make the latter into warnings or, better, errors. But stuff that is in the middle category you don’t want to restrict unless there is a clear way to work around it.» Eric Lippert, May 14, 2008
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BillWoodruff wrote: I get a glimpse of your shadow going around a corner
You are generous as always!
There are some corners I probably should not be followed:
public static bool If(this bool b, Action action)
public static void IfElse(this bool b, Action ifTrue, Action ifFalse)
etc.
Let's just call those "experiments."
Marc
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Ha! But then there is value in experiments:
public static void ForEach<T>(this IEnumerable<T> sequence, Action<T, int> action)
{
var index = 0;
foreach(T item in sequence) {
action(item, index);
index++;
}
}
For example, I am curious if I could find value in (probably with a different body implementation):
public static async Task ForEachAsync<T>(this IEnumerable<T> sequence, Func<T, Task> actionAsync)
{
foreach(T item in sequence) await actionAsync(item);
}
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Is that a Smalltalk influence I detect?
In Smalltalk, there are no control flow statements beyond sending messages. However, the boolean object responds to the messages ifTrue: and ifTrue:Else:
(x < 3) ifTrue: [ x <- 3 ].
(x < 3) ifTrue: [ x <- 3 ] Else: [ x <- x + 1 ].
And of course similar constructs such as:
(x > 0) whileTrue: [ x <- x - 1 ].
Here [] denotes a block of code (similar to a closure) and <- denotes assignment.
"If you don't fail at least 90 percent of the time, you're not aiming high enough."
Alan Kay.
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Definitely, cancer in my world. My goal is to build quality software that any level of developer can easily understand and change, if needed. Hey, I might die tomorrow. I don't run after the newest thing and don't try to be fancy or cute.
It is probably popular because organizations, such as MSFT, bring out new features to get more people on board using their products. Young people just starting out have a difficult time getting established, plus they like to be fashionable; so they try to code fancy with all the new stuff, to make the big money.
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The newest thing? It has been around for almost 10 years... 
The paradigm itself, readable, no side-effects code making heavy use of lambda's (or anonymous function) has been around almost as long as programming. It's called functional programming.
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Sander Rossel wrote: The newest thing? It has been around for almost 10 years...
Exactly. I'm baffled by the people in the thread calling this style a new thing 
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As LISP came out in 1958, it makes it a pretty old thing for programming. Venerable even.
"If you don't fail at least 90 percent of the time, you're not aiming high enough."
Alan Kay.
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It seems I may be in the minority, but I don't find that (or predicates in general) unreadable.
/ravi
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As others have said, it might give you "nerd points", but IMO it is the C# equivalent of APL one-liners - easy to write, impossible to debug or understand 6 months down the line.
Under some circumstances, this coding style may produce faster code, but that remains to be measured.
If you have an important point to make, don't try to be subtle or clever. Use a pile driver. Hit the point once. Then come back and hit it again. Then hit it a third time - a tremendous whack.
--Winston Churchill
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Daniel Pfeffer wrote: impossible to debug or understand 6 months down the line.
I'd have to disagree with that - I've got LINQ code going back eight years which is still perfectly understandable. It tends to be easier to read than the equivalent imperative code, especially if you try to squeeze all of the filtering, grouping, sorting and projecting code into one method to try to make it go faster.
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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harold aptroot wrote: Is this style cancer?
Not in my opinion.
So what you'd have is (a bit cleaned up and assumptions made):
foreach(var stuff in someStuff)
{
if (stuff.c != "What")
{
Hell(stuff.d + "The");
}
}
harold aptroot wrote: Side question, why is this style popular?
I think, given the above example, the answer to that is obvious. But if you want it enumerated (hardeeharhar):
1) Easier to understand the logic
2) Simpler code
harold aptroot wrote: I file this firmly under "stupid one-liner 'clever' code with no benefits to compensate".
Sure, it can be abused, but for me, the Linq statement is so much more readable and understandable, in a very short order of time, than the longer format.
Consider also some order advantages:
someStuff.Where(c => c != What).Select(d => d + The).OrderByDescending(q => q.CreateDate).Foreach(e => Hell(e));
What a PITA to have to create yet another list to reverse the order, and if you're abstaining from Linq altogether, you'd probably have to call a method to re-order the list on the desired field. More kruft, more complexity, more things to go wrong, more hard to understand imperative code.
Furthermore, if you need to change the order, the above "long" code example breaks, because now you have to create a separate list of the filtered items so you can then sort that -- I assume you wouldn't want to sort the unfiltered list!
So, add another item to the reason the "style cancer" is better:
3) more maintainable
The style cancer, as you call it, is very much like functional programming, where each function results in an output that you pipe to the next function as its input. It's a much much cleaner style.
Marc
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Exactly, well put 
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/ravi
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Ok OrderByDescending is convenient and having to retroactively put in sorting into normal code is annoying. That doesn't sell it for me. It's still "codegolfing but with longer method names" to me.
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harold aptroot wrote: "codegolfing"
Strange thing there, Harold; last Sunday's crossword puzzle had, as its long-tail-quote, something former US Prez Gerald Ford supposedly said:
"I am not getting better playing golf because I hit fewer spectators"
Have you ever looked at the XML the WCF serializer generates: object-name prefixes and suffixes can total twenty characters and more. It has become my habit to write long descriptive names in code, even though I am a solo act; part of that is because I want any students who may see the code to encounter such long mnemonic names ... and, partly because I am a speed touch typist, so the perceived "cost" of typing longer names is minimal ... and, of course, ReSharper and the VS editor make name completion a snaparoo.
cheers, Bill
«There is a spectrum, from "clearly desirable behaviour," to "possibly dodgy behavior that still makes some sense," to "clearly undesirable behavior." We try to make the latter into warnings or, better, errors. But stuff that is in the middle category you don’t want to restrict unless there is a clear way to work around it.» Eric Lippert, May 14, 2008
modified 17-Jul-16 12:47pm.
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harold aptroot wrote: t's still "codegolfing but with longer method names" to me.
Well, if readability, simplicity, maintainability, and a more functional programming syntax style don't sell you, then I don't know what will.
And an FP style is often times better because those "long method names" are descriptive of what is happening, rather than having to look at code to figure out what is happened.
Marc
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