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Property getters and setters
...g to backup the computed property. Try this:
class Point {
private var _x: Int = 0 // _x -> backingX
var x: Int {
set { _x = 2 * newValue }
get { return _x / 2 }
}
}
Specifically, in the Swift REPL:
15> var pt = Point()
pt: Point = {
_x = 0
}
16> pt.x = 10...
Unique fields that allow nulls in Django
...pty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None:
class FooForm(forms.ModelForm):
class Meta:
model = Foo
def clean_bar(self):
return self.cleaned_data['bar'] or None
class FooAdmin(admin.ModelAdmin...
How to check if a value exists in a dictionary (python)
...
it wasn't necesarry after all, unless run on bigger dict. I guess overhead in values() is caused by copying the value list and in viewvalues() by maintaining the view alive.
– soulcheck
Nov 21 '11 at 17:12
...
Debug vs Release in CMake
...
With CMake, it's generally recommended to do an "out of source" build. Create your CMakeLists.txt in the root of your project. Then from the root of your project:
mkdir Release
cd Release
cmake -DCMAKE_BUILD_TYPE=Release ..
make
And for Debug (...
Substitute multiple whitespace with single whitespace in Python [duplicate]
...ce characters that are combined.
To match unicode whitespace:
import re
_RE_COMBINE_WHITESPACE = re.compile(r"\s+")
my_str = _RE_COMBINE_WHITESPACE.sub(" ", my_str).strip()
To match ASCII whitespace only:
import re
_RE_COMBINE_WHITESPACE = re.compile(r"(?a:\s+)")
_RE_STRIP_WHITESPACE = re.co...
Javascript : natural sort of alphanumerical strings
...by the value of a certain key in an array of objects. It can also automatically identify and sort strings of: currencies, dates, currency, and a bunch of other things.
Surprisingly, it's also only 1.6kB when gzipped.
share
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How to make ng-repeat filter out duplicate results
...sion of ui utils, you can just include ui.unique on its own. use bower install just for the module.
– Learning stats by example
Feb 11 '15 at 19:59
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django : using select_related and get_object_or_404 together
Is there any way of using get_object_or_404 and select_related together or any other way to achieve the result of using these two together(except from putting it in try/except)??
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How can I call a custom Django manage.py command directly from a test driver?
...ts.
But if you by some reason cannot decouple logic form command you can call it from any code using call_command method like this:
from django.core.management import call_command
call_command('my_command', 'foo', bar='baz')
...
Error in strings.xml file in Android
... This can cause a problem when you have a lot of strings and use replace all. See my answer.
– Dan Bray
Oct 23 '18 at 14:08
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