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What's a correct and good way to implement __hash__()?
...be integers, and there aren't too many of them, I suppose you could potentially run slightly faster with some home-rolled hash, but it likely wouldn't be as well distributed. hash((self.attr_a, self.attr_b, self.attr_c)) is going to be surprisingly fast (and correct), as creation of small tuples is ...
How to check if all elements of a list matches a condition?
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The best answer here is to use all(), which is the builtin for this situation. We combine this with a generator expression to produce the result you want cleanly and efficiently. For example:
>>> items = [[1, 2, 0], [1, 2, 0], [1, 2, 0]]
>>...
How does an underscore in front of a variable in a cocoa objective-c class work?
...to-generated accessor (for the property) knows which ivar to use. Specifically, in your implementation file, your synthesize should look like this:
@synthesize missionName = _missionName;
More generically, this is:
@synthesize propertyName = _ivarName;
...
Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
Dynamically Changing log4j log level
What are the different approaches for changing the log4j log level dynamically, so that I will not have to redeploy the application. Will the changes be permanent in those cases?
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PDO closing connection
...
close the connection, you need to destroy the object by ensuring that
all remaining references to it are deleted--you do this by assigning
NULL to the variable that holds the object. If you don't do this
explicitly, PHP will automatically close the connection when your
script ends.
Note...
Any reason not to use '+' to concatenate two strings?
... Tuple would be faster - the code was just an example :) Usually long multiple string inputs are dynamic.
– Mikko Ohtamaa
Apr 6 '12 at 12:52
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How to force ASP.NET Web API to always return JSON?
... use this method but the one below using GlobalConfiguration...Clear() actually works.
– seangwright
May 7 '15 at 20:52
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PowerShell script to return versions of .NET Framework on a machine?
...t). It also outputs both Client and Full on 4.0 (if you have them both installed):
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -recurse |
Get-ItemProperty -name Version,Release -EA 0 |
Where { $_.PSChildName -match '^(?!S)\p{L}'} |
Select PSChildName, Version, Release
Based o...
Why is my git repository so big?
...he whole directory structure.
Edit: Here's Ian's one liner for recreating all branches in the new repo:
d1=#original repo
d2=#new repo (must already exist)
cd $d1
for b in $(git branch | cut -c 3-)
do
git checkout $b
x=$(git rev-parse HEAD)
cd $d2
git checkout -b $b $x
cd $d1
d...