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What is the purpose of the single underscore “_” variable in Python?
What is the meaning of _ after for in this code?
5 Answers
5
...
Java: Calling a super method which calls an overridden method
... we call the method
over here...
| +----------------+
_____/ | super |
/ +----------------+
| +------------+ | bar() |
| | this | | foo() |
| +------------+ | method0() |
+-> | @method1() |...
How do I get the full path of the current file's directory?
...3
For the directory of the script being run:
import pathlib
pathlib.Path(__file__).parent.absolute()
For the current working directory:
import pathlib
pathlib.Path().absolute()
Python 2 and 3
For the directory of the script being run:
import os
os.path.dirname(os.path.abspath(__file__))
I...
Python Sets vs Lists
... as lists, except for their immutability.
Iterating
>>> def iter_test(iterable):
... for i in iterable:
... pass
...
>>> from timeit import timeit
>>> timeit(
... "iter_test(iterable)",
... setup="from __main__ import iter_test; iterable = set(range(1...
Are PHP include paths relative to the file or the calling code?
...f you want to make it matter, and do an include relative to B.php, use the __FILE__ constant (or __DIR__ since PHP 5.2 IIRC) which will always point to the literal current file that the line of code is located in.
include(dirname(__FILE__)."/C.PHP");
...
How to get the parent dir location
...bspath doesn't validate anything, so if we're already appending strings to __file__ there's no need to bother with dirname or joining or any of that. Just treat __file__ as a directory and start climbing:
# climb to __file__'s parent's parent:
os.path.abspath(__file__ + "/../../")
That's far less...
How to get everything after a certain character?
...then substr grabs everything from that index plus 1, onwards.
$data = "123_String";
$whatIWant = substr($data, strpos($data, "_") + 1);
echo $whatIWant;
If you also want to check if the underscore character (_) exists in your string before trying to get it, you can use the following:
i...
What is the id( ) function used for?
...d and user does not see them:
class democlass:
classvar = 24
def __init__(self, var):
self.instancevar1 = var
self.instancevar2 = 42
def whoreferencesmylocalvars(self, fromwhere):
return {__l__: {__g__
for __g__ in fromwhere
...
Understanding the main method of python [duplicate]
...is almost unique to the language(*).
The semantics are a bit subtle. The __name__ identifier is bound to the name of any module as it's being imported. However, when a file is being executed then __name__ is set to "__main__" (the literal string: __main__).
This is almost always used to separate...
Set Django IntegerField by choices=… name
...epresents the proper integer.
Like so:
LOW = 0
NORMAL = 1
HIGH = 2
STATUS_CHOICES = (
(LOW, 'Low'),
(NORMAL, 'Normal'),
(HIGH, 'High'),
)
Then they are still integers in the DB.
Usage would be thing.priority = Thing.NORMAL
...