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How to perform Callbacks in Objective-C
...ust meant, in you're .m file. You'd have a separate class, let's call it "Foo". Foo would have a "MyClass *myClass" variable, and at some point Foo would say "[myClass setDelegate:self]". At any point after that, if anyone including foo invoked the doSomethingMethod on that instance of MyClass, foo...
How can I access and process nested objects, arrays or JSON?
...as any string can be used as key in objects. The key-value pairs are also called the "properties".
Properties can be accessed either using dot notation
const value = obj.someProperty;
or bracket notation, if the property name would not be a valid JavaScript identifier name [spec], or the name is...
How to initialize static variables
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I love PHP, but it's really odd sometimes.
– Marco Demaio
Nov 10 '11 at 21:46
6
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Rename a dictionary key
... this question seems to be asking, is impractical because dict keys are usually immutable objects such as numbers, strings or tuples. Instead of trying to modify the key, reassigning the value to a new key and removing the old key is how you can achieve the "rename" in python.
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is_null($x) vs $x === null in PHP [duplicate]
...someone strongly suggested that I use is_null() instead as it is specifically designed for the null-evaluation purpose. He also started talking about math or something.
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typedef fixed length array
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@sh1: On all modern real-world ABIs I'm aware of - even ones where misaligned access is very expensive - structures don't get stronger alignment requirements than their members would have without the structure. Of course OP or anyone ...
Determine the type of an object?
...object, and isinstance() to check an object’s type against something. Usually, you want to use isistance() most of the times since it is very robust and also supports type inheritance.
To get the actual type of an object, you use the built-in type() function. Passing an object as the only param...
How do I save and restore multiple variables in python?
...; from klepto.archives import file_archive
>>> db = file_archive('foo.txt')
>>> db['1'] = 1
>>> db['max'] = max
>>> squared = lambda x: x**2
>>> db['squared'] = squared
>>> def add(x,y):
... return x+y
...
>>> db['add'] = add
>>...
Remove excess whitespace from within a string
I receive a string from a database query, then I remove all HTML tags, carriage returns and newlines before I put it in a CSV file. Only thing is, I can't find a way to remove the excess white space from between the strings.
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How to update PATH variable permanently from Windows command line?
... do this can be found on MSDN. The key extract is this:
To programmatically add or modify system environment variables, add them to the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment registry key, then broadcast a WM_SETTINGCHANGE message with lParam set to the s...