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Null coalescing in powershell
... evaluated
Null Conditional Assignment
$x = $null
$x ??= 100 # $x is now 100
$x ??= 200 # $x remains 100
Ternary Operator
$true ? "this value returned" : "this expression not evaluated"
$false ? "this expression not evaluated" : "this value returned"
Previous Versions:
No need for ...
Converting datetime.date to UTC timestamp in Python
...eturn (td.microseconds + (td.seconds + td.days * 86400) * 10**6) / 10**6
now = datetime.utcnow()
print now
print totimestamp(now)
Beware of floating-point issues.
Output
2012-01-08 15:34:10.022403
1326036850.02
How to convert an aware datetime object to POSIX timestamp
assert dt.tzinfo is n...
How to get the number of days of difference between two dates on mysql?
...-14 11:00:00');
returns 1
select timestampdiff(DAY, '2016-04-13 11:00:00', now()); returns how many full 24h days has passed since 2016-04-13 11:00:00 until now.
Hope it will help someone, because at first it isn't much obvious why datediff returns values which seems to be unexpected or wrong.
...
Min/Max of dates in an array?
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IE <9 can die, and indeed, it now accounts for only 9.3% of global browser use as of April 2013.
– wprl
May 23 '13 at 15:58
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Is there an interactive way to learn Vim? [closed]
...that didn't involve a wall of text, or scrolling through vimtutor without knowing the commands to do so. I wondered if anything else existed for such a purpose.
...
EF5: Cannot attach the file ‘{0}' as database '{1}'
...
@Peter Ok, Added the database and now I see my 2 contexts. When I delete from this view I get a new error : 'can not retrieve data access level for this database'. I was able to get around this by using the command prompt.
– nVentimiglia...
Extract traceback info from an exception object
Given an Exception object (of unknown origin) is there way to obtain its traceback? I have code like this:
5 Answers
...
Add custom icons to font awesome
...ab, fas, far, fal) you'll be at greater risk of a naming conflict—if not now, then possibly in the future as we continue adding icons with those standard prefixes. Using a custom prefix won't make an svg any less likely to "fit into the website"—but I'm not sure what you mean by that phrase, so ...
How to override and extend basic Django admin templates?
... This answer was very good for the older Django versions. But as of now, Another answer by Cheng is more relevant. stackoverflow.com/a/29997719/7344164
– DevLoverUmar
Jul 15 at 5:12
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MemoryCache does not obey memory limits in configuration
... this._idx ^= 1;
this._cacheSizeSampleTimes[this._idx] = DateTime.UtcNow;
this._cacheSizeSamples[this._idx] = ref2.ApproximateSize;
IMemoryCacheManager manager = s_memoryCacheManager;
if (manager != null)
{
manager.UpdateCacheSize(this._cacheSizeSamples[this._idx], this._...