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Why use 'virtual' for class properties in Entity Framework model definitions?
... and more efficient change tracking. See What effect(s) can the virtual keyword have in Entity Framework 4.1 POCO Code First? for a more thorough discussion.
Edit to clarify "create a proxy around":
By "create a proxy around" I'm referring specifically to what the Entity Framework does. The Entity ...
HashMap get/put complexity
...HashMap stirs the hash before using it, to mix entropy from throughout the word into the bottom bits, which is where it's needed for all but the hugest hashmaps. That helps deal with hashes that specifically don't do that themselves, although i can't think of any common cases where you'd see that.
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What is the difference between currying and partial application?
...an do this:
f2 = Curry(Add);
f3 = f2(7);
f3(5); // returns 12
In other words, "currying" and "partial application" are two totally different functions. Currying takes exactly 1 input, whereas partial application takes 2 (or more) inputs.
Even though they both return a function as output, the re...
What is Weak Head Normal Form?
...ts, like (+) 2 or sqrt
A lambda-expression: \x -> expression
In other words, the head of the expression (i.e. the outermost function application) cannot be evaluated any further, but the function argument may contain unevaluated expressions.
Examples of WHNF:
3 : take 2 [2,3,4] -- outermost...
how do you filter pandas dataframes by multiple columns
...
hi it's a single key, just a word, that would correspond to the gender (male, or female) or year (13, 14) Didn't know you could have a tuple of keys. Could you share an example of when and how you would do this?
– yoshiserry
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What is the JavaScript >>> operator and how do you use it?
...0 >>>0 === 0 evaluates as true? even though lemons is obviously a word..?
– Zze
Mar 27 '18 at 23:03
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Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
...e same cost because they have to be validated against the schema. In other words this is a complete wash.
For item 4, when you specify specific columns, your query plan cache could get larger but only if you are dealing with different sets of columns (which is not what you've specified). In this ca...
How to add an extra source directory for maven to compile and include in the build jar?
...c/bootstrap directory that I want to include in my build process, in other words, I want maven to compile and include the sources there in my build. How!?
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Which equals operator (== vs ===) should be used in JavaScript comparisons?
...f Type(constructor) is not Object, throw a TypeError exception.
With other words, if String wouldn't be of type Object it couldn't be used with the new operator.
new always returns an Object, even for String constructors, too. And alas! The value semantics for strings (see step 11) is lost.
And thi...
c++11 Return value optimization or move? [duplicate]
...: Sounds like a bug in the documentation, specifically, it sounds like the wording of the documentation wasn't updated for C++11. File a bug? @JonathanWakely?
– Kerrek SB
Apr 21 at 14:08
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