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python design patterns [closed]
...for their existence.
It's nothing more than
class Null(object):
def __init__(self, *args, **kwargs):
"Ignore parameters."
return None
def __call__(self, *args, **kwargs):
"Ignore method calls."
return self
def __getattr__(self, mname):
"Ignore...
How do I use extern to share variables between source files?
...ler is informed that a
variable exists (and this is its type); it does not allocate the
storage for the variable at that point.
A variable is defined when the compiler allocates the storage for
the variable.
You may declare a variable multiple times (though once is sufficient);
you may only defin...
Java “lambda expressions not supported at this language level”
...: android { compileOptions { sourceCompatibility JavaVersion.VERSION_1_8 targetCompatibility JavaVersion.VERSION_1_8 } }
– BaDo
Sep 25 '15 at 2:30
...
C dynamically growing array
...ynamic array implementations work by starting off with an array of some (small) default size, then whenever you run out of space when adding a new element, double the size of the array. As you can see in the example below, it's not very difficult at all: (I've omitted safety checks for brevity)
type...
What is the difference between __dirname and ./ in node.js?
...ere in relation to your current directory, is there any reason to use the __dirname variable instead of just a regular ./ ? I've been using ./ thus far in my code and just discovered the existence of __dirname , and essentially want to know whether it would be smart to convert my ./'s to that, a...
How can I scale an image in a CSS sprite
...http://css-tricks.com/css-sprites/ , it talks about how can I crop off a smaller image from 1 bigger image. Can you please tell me if it is possible/how I can crop off a smaller image and then scale the cropped off region before I lay it out?
...
Why are function pointers and data pointers incompatible in C/C++?
...ry but C doesn't limit itself to only certain types of architectures if at all possible.
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Removing multiple keys from a dictionary safely
...
Why not like this:
entries = ('a', 'b', 'c')
the_dict = {'b': 'foo'}
def entries_to_remove(entries, the_dict):
for key in entries:
if key in the_dict:
del the_dict[key]
A more compact version was provided by mattbornski using dict.pop()
...
How to make PDF file downloadable in HTML link?
...
header("Content-Length: " . filesize($file));
flush(); // this doesn't really matter.
$fp = fopen($file, "r");
while (!feof($fp))
{
echo fread($fp, 65536);
flush(); // this is essential for large downloads
}
fclose($fp);
PS: and obviously run some sanity checks on the "file" variable t...
Installing SciPy with pip
It is possible to install NumPy with pip using pip install numpy .
15 Answers
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