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What does the variable $this mean in PHP?
...P.html
Example:
<?php
class Person {
public $name;
function __construct( $name ) {
$this->name = $name;
}
};
$jack = new Person('Jack');
echo $jack->name;
This stores the 'Jack' string as a property of the object created.
...
not None test in Python [duplicate]
...r of the latter two, since val could potentially be of a type that defines __eq__() to return true when passed None.
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Chrome, Javascript, window.open in new tab
...
As of 9/29/2014, latest Firefox ESR and IE 11 open _blank or window.open links in a new window when the js calls use _blank as the window name. Current Chrome isn't that simple. I tested opening a new window passing top, left, width, height, toolbar, location, directories, st...
How do you create different variable names while in a loop? [duplicate]
...can do this is with exec(). For example:
for k in range(5):
exec(f'cat_{k} = k*2')
>>> print(cat_0)
0
>>> print(cat_1)
2
>>> print(cat_2)
4
>>> print(cat_3)
6
>>> print(cat_4)
8
Here I am taking advantage of the handy f string formatting in Pytho...
Inject errors into already validated form?
...
Form._errors can be treated like a standard dictionary. It's considered good form to use the ErrorList class, and to append errors to the existing list:
from django.forms.utils import ErrorList
errors = form._errors.setdefault("m...
Writing unit tests in Python: How do I start? [closed]
...est):
import unittest
class LearningCase(unittest.TestCase):
def test_starting_out(self):
self.assertEqual(1, 1)
def main():
unittest.main()
if __name__ == "__main__":
main()
Example 2 (pytest):
def test_starting_out():
assert 1 == 1
Assuming that both files are name...
how to return index of a sorted list? [duplicate]
...ray([2,3,1,4,5])
>>> vals
array([2, 3, 1, 4, 5])
>>> sort_index = numpy.argsort(vals)
>>> sort_index
array([2, 0, 1, 3, 4])
If not available, taken from this question, this is the fastest method:
>>> vals = [2,3,1,4,5]
>>> sorted(range(len(vals)), key=...
Why use def main()? [duplicate]
...tion could be:
import sys
def main(argv):
# My code here
pass
if __name__ == "__main__":
main(sys.argv)
This means you can call main() from other scripts (or interactive shell) passing custom parameters. This might be useful in unit tests, or when batch-processing. But remember that t...
Conditional compilation and framework targets
...rgetFrameworkVersion.Replace('v', '')) >= 2.0 ">$(DefineConstants)NET_20_OR_GREATER, </DefineConstants>
<DefineConstants Condition=" $(TargetFrameworkVersion.Replace('v', '')) >= 3.5 ">$(DefineConstants)NET_35_OR_GREATER</DefineConstants>
<DefineConstants Condition=...
When to use NSInteger vs. int
...amic typedef*s to one of these types, and they are defined like this:
#if __LP64__ || TARGET_OS_EMBEDDED || TARGET_OS_IPHONE || TARGET_OS_WIN32 || NS_BUILD_32_LIKE_64
typedef long NSInteger;
typedef unsigned long NSUInteger;
#else
typedef int NSInteger;
typedef unsigned int NSUInteger;
#endif
Wit...