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Referring to the null object in Python
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SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
Ignore python multiple return value
...add gettext functionality to someone else's code (that defines a function called '_') so it should be banned
– nosklo
Jan 11 '09 at 13:32
28
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django - why is the request.POST object immutable?
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It's a bit of a mystery, isn't it? Several superficially plausible theories turn out to be wrong on investigation:
So that the POST object doesn't have to implement mutation methods? No: the POST object belongs to the django.http.QueryDict class, which implements a full set ...
Batch File; List files in directory, only filenames?
...s is probably a very simple question, but I'm having trouble with it. Basically, I am trying to write a Batch File and I need it to list all the files in a certain directory. The dir command will do this, but it also gives a bunch of other information; I want it to list ONLY the file names and e...
What does the restrict keyword mean in C++?
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A restrict-qualified pointer (or reference)...
! ...is basically a
promise to the compiler that for the
scope of the pointer, the target of the pointer will only
be accessed through that pointer (and pointers copied
from it).
In C++ compilers that support it i...
uint8_t vs unsigned char
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It documents your intent - you will be storing small numbers, rather than a character.
Also it looks nicer if you're using other typedefs such as uint16_t or int32_t.
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Define a lambda expression that raises an Exception
...ur goal is to avoid a def, this obviously doesn't cut it. It does, however allow you to conditionally raise exceptions, e.g.:
y = lambda x: 2*x if x < 10 else raise_(Exception('foobar'))
Alternatively you can raise an exception without defining a named function. All you need is a strong stom...
What does `m_` variable prefix mean?
...'re using something like intelliSense, you can start with m_ and a list of all your member variables are shown. Part of Hungarian notation, see the part about scope in the examples here.
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imp...
Elasticsearch query to return all records
I have a small database in Elasticsearch and for testing purposes would like to pull all records back. I am attempting to use a URL of the form...
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Is there a difference between “==” and “is”?
... a
True
In your case, the second test only works because Python caches small integer objects, which is an implementation detail. For larger integers, this does not work:
>>> 1000 is 10**3
False
>>> 1000 == 10**3
True
The same holds true for string literals:
>>> "a" i...