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What's the difference between IQueryable and IEnumerable
...;>), which can be thought of as "is the 'Age' property > 18".
This allows things like LINQ-to-SQL to exist because they can parse the expression tree and convert it into equivalent SQL. And because the provider doesn't need to execute until the IQueryable is enumerated (it implements IEnum...
How to remove item from list in C#?
...== 2);
resultList.Remove(itemToRemove);
When you are not sure the item really exists you can use SingleOrDefault. SingleOrDefault will return null if there is no item (Single will throw an exception when it can't find the item). Both will throw when there is a duplicate value (two items with the s...
equals vs Arrays.equals in Java
... it, ever.
That said, it's not "broken" as in "someone has done it in a really wrong way" — it's just doing what's defined and not what's usually expected. So for purists: it's perfectly fine, and that also means, don't use it, ever.
Now the expected behaviour for equals is to compare data. The ...
In Python, how can you load YAML mappings as OrderedDicts?
...
Update: In python 3.6+ you probably don't need OrderedDict at all due to the new dict implementation that has been in use in pypy for some time (although considered CPython implementation detail for now).
Update: In python 3.7+, the insertion-order preservation nature of dict objects h...
What is the best way to create constants in Objective-C
...he file in the Reddit-Prefix.pch file to make the constants available to all the files. Is it a good way of doing things? Also, I've done my research and found several methods to create constants, but I don't know which one to use:
...
Printing hexadecimal characters in C
... signed on your system. In C, vararg functions such as printf will promote all integers smaller than int to int. Since char is an integer (8-bit signed integer in your case), your chars are being promoted to int via sign-extension.
Since c0 and 80 have a leading 1-bit (and are negative as an 8-bit ...
Java Name Hiding: The Hard Way
... of working with the reflection API.
The downside is that this code is really horrible! For me, it generates a warning, and that's a good thing in general. But since it's working around a problem that is otherwise thoroughly impractical, adding a
@SuppressWarnings("static-access")
at an approp...
How to delay the .keyup() handler until the user stops typing?
...
I use this small function for the same purpose, executing a function after the user has stopped typing for a specified amount of time or in events that fire at a high rate, like resize:
function delay(callback, ms) {
var timer = 0;
...
Write to UTF-8 file in Python
...
I believe the problem is that codecs.BOM_UTF8 is a byte string, not a Unicode string. I suspect the file handler is trying to guess what you really mean based on "I'm meant to be writing Unicode as UTF-8-encoded text, but you've given me a byte string!"
Try writin...
Should I use multiplication or division?
...wer compared to the lower overhead of the VM. Remember that compilers generally cannot optimize floating point much in order to guarantee precision.
– rasmus
Sep 14 '12 at 7:22
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