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Dynamic type languages versus static type languages
...ust another property of a datum, like the length of an array, or the first character of a string. And many dynamically typed languages also allow you to write out things like "error: the first character of this string should be a 'z'".
Another thing is that dynamically typed languages have the type ...
Understanding __get__ and __set__ and Python descriptors
...th the Temperature class). For example:
temp=Temperature()
temp.celsius #calls celsius.__get__
Accessing the property you assigned the descriptor to (celsius in the above example) calls the appropriate descriptor method.
instance in __get__ is the instance of the class (so above, __get__ would r...
Undo part of unstaged changes in git
...ier if you use a good editor mode or plugin, which may provide support for selecting lines directly to revert, as -p can be a bit clumsy to use sometimes. I use Magit, an Emacs mode that is very helpful for working with Git. In Magit, you can run magit-status, find the diffs for the changes that you...
Python dictionary from an object's fields
...a dictionary from an arbitrary object, it's sufficient to use __dict__. Usually, you'll declare your methods at class level and your attributes at instance level, so __dict__ should be fine. For example:
>>> class A(object):
... def __init__(self):
... self.b = 1
... self.c = 2
....
Loop through all the resources in a .resx file
...et.OfType<DictionaryEntry>(). Using LINQ allows you, for example, to select resources based on their index (int) instead of key (string):
ResourceSet resourceSet = Resources.ResourceManager.GetResourceSet(CultureInfo.CurrentUICulture, true, true);
foreach (var entry in resourceSet.OfType<D...
How to create module-wide variables in Python? [duplicate]
...
Here is what is going on.
First, the only global variables Python really has are module-scoped variables. You cannot make a variable that is truly global; all you can do is make a variable in a particular scope. (If you make a variable inside the Python interpreter, and then import other mo...
How to check if the user can go back in browser history or not
... if the 'beforeunload' fired.
var $window = $(window),
$trigger = $('.select_your_link'),
fallback = 'your_fallback_url';
hasHistory = false;
$window.on('beforeunload', function(){
hasHistory = true;
});
$trigger.on('click', function(){
window.history.go(-1);
setTimeout(...
Tricks to manage the available memory in an R session
...
I make aggressive use of the subset parameter with selection of only the required variables when passing dataframes to the data= argument of regression functions. It does result in some errors if I forget to add variables to both the formula and the select= vector, but it sti...
Can a decorator of an instance method access the class?
I have something roughly like the following. Basically I need to access the class of an instance method from a decorator used upon the instance method in its definition.
...
How do exceptions work (behind the scenes) in c++
...
Instead of guessing, I decided to actually look at the generated code with a small piece of C++ code and a somewhat old Linux install.
class MyException
{
public:
MyException() { }
~MyException() { }
};
void my_throwing_function(bool throwit)
{
if (...