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What is the purpose of willSet and didSet in Swift?
... = 0 {
didSet {
print("The value of myProperty changed from \(oldValue) to \(myProperty)")
}
}
}
myProperty prints its old and new value every time it is modified. With just getters and setters, I would need this instead:
class Foo {
var myPropertyValue: Int = ...
How to remove duplicate values from a multi-dimensional array in PHP
How can I remove duplicate values from a multi-dimensional array in PHP?
19 Answers
19...
How to grant remote access permissions to mysql server for user?
...
This grants root access with the same password from any machine in *.example.com:
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%.example.com'
IDENTIFIED BY 'some_characters'
WITH GRANT OPTION;
FLUSH PRIVILEGES;
If name resolution is not going to work, you may also ...
Exporting functions from a DLL with dllexport
I'd like a simple example of exporting a function from a C++ Windows DLL.
4 Answers
4
...
Convert string in base64 to image and save on filesystem in Python
...odernizing this example to Python 3, which removed arbitrary codec support from string/bytes .encode() and .decode() functions:
# For both Python 2.7 and Python 3.x
import base64
with open("imageToSave.png", "wb") as fh:
fh.write(base64.decodebytes(img_data))
...
Why isn't Python very good for functional programming? [closed]
...e, powerful expression syntax (Python's simple block syntax prevents Guido from adding it)
No pattern matching and no tail recursion mean your basic algorithms have to be written imperatively. Recursion is ugly and slow in Python.
A small list library and no functional dictionaries mean that yo...
Are static class variables possible in Python?
...ev points out, this creates a class-level i variable, but this is distinct from any instance-level i variable, so you could have
>>> m = MyClass()
>>> m.i = 4
>>> MyClass.i, m.i
>>> (3, 4)
This is different from C++ and Java, but not so different from C#, where...
HashMap with multiple values under the same key
...dd(new Person("Bob Jones"));
peopleByForename.put("Bob", people);
// read from it
List<Person> bobs = peopleByForename["Bob"];
Person bob1 = bobs[0];
Person bob2 = bobs[1];
The disadvantage with this approach is that the list is not bound to exactly two values.
2. Using wrapper class
// d...
What is the difference between HTTP_HOST and SERVER_NAME in PHP?
...
The HTTP_HOST is obtained from the HTTP request header and this is what the client actually used as "target host" of the request. The SERVER_NAME is defined in server config. Which one to use depends on what you need it for. You should now however rea...
Is it good practice to make the constructor throw an exception? [duplicate]
... throw Exception it is difficult for the caller to separate this exception from any number of other possible declared and undeclared exceptions. This makes error recovery difficult, and if the caller chooses to propagate the Exception, the problem just spreads.
1 - Some people may disagree, but ...