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Why can't I overload constructors in PHP?
I have abandoned all hope of ever being able to overload my constructors in PHP, so what I'd really like to know is why .
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Using python's eval() vs. ast.literal_eval()?
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datamap = eval(raw_input('Provide some data here: ')) means that you actually evaluate the code before you deem it to be unsafe or not. It evaluates the code as soon as the function is called. See also the dangers of eval.
ast.literal_eval raises an exception if the input isn't a valid Python dat...
C#: Printing all properties of an object [duplicate]
Is there a method built in to .NET that can write all the properties and such of an object to the console? Could make one using reflection of course, but I'm curious to if this already exists... especially since you can do it in Visual Studio in the Immediate Window. There you can an object name (wh...
How to get a complete list of object's methods and attributes?
...butes, the short answer is: no. The problem is that the attributes are actually defined as the arguments accepted by the getattr built-in function. As the user can reimplement __getattr__, suddenly allowing any kind of attribute, there is no possible generic way to generate that list. The dir functi...
Unpacking array into separate variables in JavaScript
...nd I've done it before. I just can't remember how, or what exactly it was called.
7 Answers
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Is arr.__len__() the preferred way to get the length of an array in Python?
...ples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to explicitly implement a public...
Visual Studio 2012 Express is suddenly “incompatible with this version of Windows”?
...e same message on Visual Studio 2012 Premium (on PC where Windows 7 re-installed in last month) - the suggested fix was "Update for Microsoft Visual Studio 2012 (KB2781514)" which seems to have fixed it
www.microsoft.com/en-us/download/details.aspx?id=36020
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What would a “frozen dict” be?
...).
The most common reason to want such a type is when memoizing function calls for functions with unknown arguments. The most common solution to store a hashable equivalent of a dict (where the values are hashable) is something like tuple(sorted(kwargs.iteritems())).
This depends on the sorting n...
How to make a chain of function decorators?
...her object
scream = shout
# Notice we don't use parentheses: we are not calling the function,
# we are putting the function "shout" into the variable "scream".
# It means you can then call "shout" from "scream":
print(scream())
# outputs : 'Yes!'
# More than that, it means you can remove the old...
Hashing a string with Sha256
...e you don't use the same string encoding. The link you put for the on-line web site that computes SHA256 uses UTF8 Encoding, while in your example you used Unicode Encoding. They are two different encodings, so you don't get the same result. With the example above you get the same SHA256 hash of the...