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Ruby send vs __send__
I understand the concept of some_instance.send but I'm trying to figure out why you can call this both ways. The Ruby Koans imply that there is some reason beyond providing lots of different ways to do the same thing. Here are the two examples of usage:
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How can I count the occurrences of a list item?
...1, 4, 1].count(1)
3
Don't use this if you want to count multiple items. Calling count in a loop requires a separate pass over the list for every count call, which can be catastrophic for performance. If you want to count all items, or even just multiple items, use Counter, as explained in the othe...
Is it better to use Enumerable.Empty() as opposed to new List() to initialize an IEnumerable
...uld be noticeable impact.
Enumerable.Empty does not create an object per call thus putting less load on GC.
If the code is in low-throughput location, then it boils down to aesthetic considerations though.
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Code Golf - π day
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Yeah, the ( operator alone allowed to shed 6 strokes!
– Dan Andreatta
Mar 18 '10 at 10:25
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Can I mix MySQL APIs in PHP?
...where. (Not sure whether plain old resources do that, but objects can actually take advantage of RAII to a not-insignificant degree.)
– cHao
Jul 5 '13 at 23:54
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Compile time string hashing
... string length, and the compiler is not clever enough to elide the second call. Check other answers for possible fix for this problem.
– CygnusX1
Feb 27 '16 at 16:34
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In Vim is there a way to delete without putting text in the register?
...yboard layout I have to type "<space>_d. The space is needed to actually type the ".
– Sebastián Grignoli
Mar 12 '12 at 0:01
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How to create NS_OPTIONS-style bitmask enumerations in Swift?
...tains(.secondOption) {
print("multipleOptions has SecondOption")
}
let allOptions = MyOptions(rawValue: 7)
if allOptions.contains(.thirdOption) {
print("allOptions has ThirdOption")
}
Swift 2.0
In Swift 2.0, protocol extensions take care of most of the boilerplate for these, which are now...
Django. Override save for model
...self._image_changed = True
# Or put whole logic in here
small = rescale_image(self.image,width=100,height=100)
self.image_small=SimpleUploadedFile(name,small_pic)
def get_image(self):
return self._image
image = property(get_image, set_image)
# this is ...
Insert picture into Excel cell [closed]
... appear on hover over.
Microsoft Office 365 (2019) introduced new things called comments and renamed the old comments as "notes". Therefore in the steps above do New Note instead of Insert Comment. All other steps remain the same and the functionality still exists.
There is also a $20 product fo...