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Python None comparison: should I use “is” or ==?
...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects)
In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity:
lst = [1,2,3]
lst == lst[:] # This is Tr...
Adding a cross-reference to a subheading or anchor in another page
... because it works across files, when section headings are changed, and for all builders that support cross-references.
RST, in General
The tools that convert RST files to HTML do not necessarily have a notion of collection. This is the case for instance if you rely on github to convert RST files ...
How to read and write INI file with Python3?
...
The standard ConfigParser normally requires access via config['section_name']['key'], which is no fun. A little modification can deliver attribute access:
class AttrDict(dict):
def __init__(self, *args, **kwargs):
super(AttrDict, self).__init...
I want to get the type of a variable at runtime
...that comparison return true, but it would require a few book chapters to really cover TypeTag, so I'll stop here.
Finally, maybe you don't care about the type of the variable at all. Maybe you just want to know what is the class of a value, in which case the answer is rather simple:
val x = 5
x.ge...
Call one constructor from another
...will be executed first then it will get back to the string version? (Like calling super() in Java?)
– Rosdi Kasim
Dec 18 '13 at 16:49
21
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How do I PHP-unserialize a jQuery-serialized form?
.... You do indeed need to parse the string that serialize returns. See the really popular answer below.
– Isaac Lubow
Mar 1 '19 at 2:17
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Why rename synthesized properties in iOS with leading underscores? [duplicate]
...s is an artifact of a previous version of the Objective-C runtime.
Originally, @synthesize was used to create accessors methods, but the runtime still required that instance variables had to be instantiated explicitly:
@interface Foo : Bar {
Baz *_qux;
}
@property (retain) Baz *qux;
@end
@imp...
Saving a Numpy array as an image
... Remember to scale the values to the right range for PNG, usually 0..255. The value ranges in neural networks are frequently 0..1 or -1..1.
– Tomáš Gavenčiak
Mar 31 '18 at 18:49
...
How should a model be structured in MVC? [closed]
...understand MVC-like patterns in the context of PHP-based web applications. All the external links that are used in the content are there to explain terms and concepts, and not to imply my own credibility on the subject.
The first thing that I must clear up is: the model is a layer.
Second: there ...
Using “super” in C++
... the first time C++ was standardized.
Dag Bruck proposed this extension, calling the base class "inherited." The proposal mentioned the multiple inheritance issue, and would have flagged ambiguous uses. Even Stroustrup was convinced.
After discussion, Dag Bruck (yes, the same person making the p...