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How to set a Django model field's default value to a function call / callable (e.g., a date relative
... to create a field in the class.
PRE Django 1.7
Django lets you pass a callable as the default, and it will invoke it each time, just as you want:
from datetime import datetime, timedelta
class MyModel(models.Model):
# default to 1 day from now
my_date = models.DateTimeField(default=lambda: ...
How can I prevent the “You have mixed tabs and spaces. Fix this?” message?
...
Sounds like you have the Visual Studio Productivity Power Tools 2013 installed. Go into its settings and turn off "Fix Mixed Tabs"...
Tools -> Options -> Productivity Power Tools -> Turn Extensions On/Off
If you have the default VS settings, tabs in the editor are converted to spaces...
NOT IN vs NOT EXISTS
...be the same at the moment but if either column is altered in the future to allow NULLs the NOT IN version will need to do more work (even if no NULLs are actually present in the data) and the semantics of NOT IN if NULLs are present are unlikely to be the ones you want anyway.
When neither Products...
string.IsNullOrEmpty(string) vs. string.IsNullOrWhiteSpace(string)
...ite
space besides empty string.
The term “white space” includes all characters that are not visible on
screen. For example, space, line break, tab and empty string are white
space characters*.
Reference : Here
For performance, IsNullOrWhiteSpace is not ideal but is
good. The ...
Tab Vs Space preferences in Vim
...reas with expandtab switched off, pressing the Tab key inserts a the smallest possible number of tab+space characters that matches softtabstop . (Please correct me if I'm wrong.)
...
How to break a line of chained methods in Python?
...ll with the hanging lines indented just once and the trailing paren not at all.
– Carl Meyer
Jun 23 '15 at 21:57
4
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Is Java “pass-by-reference” or “pass-by-value”?
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Java is always pass-by-value.
Unfortunately, we never handle an object at all, instead juggling object-handles called references (which are passed by value of course). The chosen terminology and semantics easily confuse many beginners.
It goes like this:
public static void main(String[] args) {
...
How to measure time in milliseconds using ANSI C?
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Doesn't this measure cpu time and not wall time?
– krs013
Feb 1 '15 at 4:53
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show 1 more comment
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Visual Studio 2010 always thinks project is out of date, but nothing has changed
... up to date) These will be the references causing the project to be perpetually "out of date".
To correct this, either remove any references to the missing files from your project, or update the references to indicate their actual locations.
Note: If using 2012 or later then the snippet should be...
NVIDIA vs AMD: GPGPU performance
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Metaphorically speaking ati has a good engine compared to nvidia.
But nvidia has a better car :D
This is mostly because nvidia has invested good amount of its resources (in money and people) to develop important libraries required fo...