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Safe (bounds-checked) array lookup in Swift, through optional bindings?
.... for Set instances, if we were to access a set element by index (SetIndex<Element>), we can run into runtime exceptions for indices that are >= startIndex and < endIndex, in which case the safe subscript fails (see e.g. this contrived example).
– dfri
...
How can I represent an 'Enum' in Python?
...version
Animal = Enum('Animal', 'ant bee cat dog')
Animal.ant # returns <Animal.ant: 1>
Animal['ant'] # returns <Animal.ant: 1> (string lookup)
Animal.ant.name # returns 'ant' (inverse lookup)
or equivalently:
class Animal(Enum):
ant = 1
bee = 2
cat = 3
dog = 4
...
Required tags not present when using Delphi XML Data Binding Wizard
...ure to understand but maybe what you are looking for is : use="optional"
<xs:element name="MyReport" type="MyReportType" />
<xs:complexType name="MyReportType">
<xs:all>
<xs:element name="Header" type="HeaderType" use="optional" />
<xs:element name="Values" type...
Swift - encode URL
...re useful (inverted) character sets:
URLFragmentAllowedCharacterSet "#%<>[\]^`{|}
URLHostAllowedCharacterSet "#%/<>?@\^`{|}
URLPasswordAllowedCharacterSet "#%/:<>?@[\]^`{|}
URLPathAllowedCharacterSet "#%;<>?[\]^`{|}
URLQueryAllowedCharacterSet "#%<>[\]...
Why is Spring's ApplicationContext.getBean considered bad?
I asked a general Spring question: Auto-cast Spring Beans and had multiple people respond that calling Spring's ApplicationContext.getBean() should be avoided as much as possible. Why is that?
...
Storing C++ template function definitions in a .CPP file
...or at least in VS2008), its the following...
In your .h file...
template<typename T>
class foo
{
public:
void bar(const T &t);
};
And in your .cpp file
template <class T>
void foo<T>::bar(const T &t)
{ }
// Explicit template instantiation
template class foo<int...
Flatten an Array of Arrays in Swift
...y(array.joined()) and the nil-removal “flattening” is equiv to array.filter{ $0 != nil }.map{ $0! }.
– Slipp D. Thompson
May 3 '17 at 0:22
...
How to remove a field completely from a MongoDB document?
...
UPDATE:
The above link no longer covers '$unset'ing. Be sure to add {multi: true} if you want to remove this field from all of the documents in the collection; otherwise, it will only remove it from the first document it finds that matches. See this for updated documentation:
https://docs.mongo...
What's the equivalent for eclipse's ALT+UP/DOWN (move line) in Visual Studio?
In Eclipse, selecting a line and pressing Alt + ↑ / ↓ will move the line up and down, a quick way to avoid copy&paste.
Is there an equivalent in Visual Studio?
...
postgresql return 0 if returned value is null
...rned only if all arguments are null. It is often
used to substitute a default value for null values when data is
retrieved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cume_dist() OVER ( ORDER BY price DESC ) FROM web_price_scan
...