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Curly braces in string in PHP
...nterpolation. From the manual:
Complex (curly) syntax
This isn't called complex because the syntax is complex, but because
it allows for the use of complex expressions.
Any scalar variable, array element or object property with a string
representation can be included via this synta...
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...
What are the rules for calling the superclass constructor?
What are the C++ rules for calling the superclass constructor from a subclass one?
10 Answers
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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.
share
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Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
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...
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...
Is there a __CLASS__ macro in C++?
Is there a __CLASS__ macro in C++ which gives the class name similar to __FUNCTION__ macro which gives the function name
...
How does a hash table work?
... book knows the title of the book and the exact title to boot, then that's all it should take. With the title, the person, with the aid of the librarian, should be able to find the book easily and quickly.
So, how can you do that? Well, obviously you can keep some kind of list of where you put each...
Ruby on Rails: Delete multiple hash keys
...re unaware of the Hash#except method ActiveSupport adds to Hash.
It would allow your code to be simplified to:
redirect_to my_path(params.except(:controller, :action, :other_key))
Also, you wouldn't have to monkey patch, since the Rails team did it for you!
...