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Getting multiple keys of specified value of a generic Dictionary?
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}
return new List<TSecond>(list); // Create a copy for sanity
}
public IList<TFirst> GetBySecond(TSecond second)
{
IList<TFirst> list;
if (!secondToFirst.TryGetValue(second, out list))
{
return EmptyFirstList;
...
Check if OneToOneField is None in Django
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To check if the (OneToOne) relation exists or not, you can use the hasattr function:
if hasattr(request.user, 'type1profile'):
# do something
elif hasattr(request.user, 'type2profile'):
# do something else
else:
# do something else
...
Credit card expiration dates - Inclusive or exclusive?
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It took me a couple of minutes to find a site that I could source for this.
The card is valid until the last day of the month indicated, after the last [sic]1
day of the next month; the card cannot be used to make a purchase if the
merchant attempts to obtain an authorization.
- S...
ssh: Could not resolve hostname [hostname]: nodename nor servname provided, or not known
... is gaining the ability to ssh into the device from outside my local network. For whatever reason, this is proving to be impossible and I haven't the slightest clue why. When I try to ssh into my server with user@hostname , I get the error:
...
Are Java static calls more or less expensive than non-static calls?
Is there any performance benefit one way or another? Is it compiler/VM specific? I am using Hotspot.
12 Answers
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How to reset or change the MySQL root password?
How do I change the MySQL root password and username in ubuntu server? Do I need to stop the mysql service before setting any changes?
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What does Visual Studio mean by normalize inconsistent line endings?
...It often happens when you copy and paste from a web page into the code editor.
Normalizing the line endings is just making sure that all of the line ending characters are consistent. It prevents one line from ending in \r\n and another ending with \r or \n; the first is the Windows line end pair, w...
Circular list iterator in Python
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Use itertools.cycle, that's its exact purpose:
from itertools import cycle
lst = ['a', 'b', 'c']
pool = cycle(lst)
for item in pool:
print item,
Output:
a b c a b c ...
(Loops forever, obviously)
In order to manually advance the iterator and pull values from it one by one, s...
What is the proper way to test if a parameter is empty in a batch file?
I need to test if a variable is set or not. I've tried several techniques but they seem to fail whenever %1 is surrounded by quotes such as the case when %1 is "c:\some path with spaces" .
...
Where is Java's Array indexOf?
...s to accomplish this using the Arrays utility class.
If the array is not sorted and is not an array of primitives:
java.util.Arrays.asList(theArray).indexOf(o)
If the array is primitives and not sorted, one should use a solution offered by one of the other answers such as Kerem Baydoğan's, Andr...