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Authorize Attribute with Multiple Roles
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Now that's an idea worthy of Mac Gyver ;)
– Christian Sauer
Jun 12 '14 at 10:47
2
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Python list subtraction operation
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Use a list comprehension:
[item for item in x if item not in y]
If you want to use the - infix syntax, you can just do:
class MyList(list):
def __init__(self, *args):
super(MyList, self).__init__(args)
def __sub__(self, other):
return self.__c...
What's Alternative to Singleton
...h as Spring or Guice? (I believe Spring also is available for .NET as well now).
That way, the framework can hold a single copy of the configuration objects, and your beans (services, DAOs, whatever) don't have to worry about looking it up.
This is the approach I usually take!
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Manipulate a url string by adding GET parameters
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This approach is good when you know that 'category' parameter is not already in the URL. If the parameter is in a URL already then PHP should take the value of the last occurrence of the parameter in the URL, so the solution of @andrewtweber still works. Ye...
How to change the default collation of a table?
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@JasomDotnet you should now use utf8mb4_unicode_ci stackoverflow.com/questions/766809/…
– baptx
Aug 7 '16 at 17:57
2
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What is the difference between native code, machine code and assembly code?
...all but everything else is about the same. Also note that the debugger is now generating the real machine code address and that it is a bit smarter about symbols. A side effect of generating debug info after generating machine code like unmanaged compilers often do. I should also mention that I t...
Calling constructors in c++ without new
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Both lines are in fact correct but do subtly different things.
The first line creates a new object on the stack by calling a constructor of the format Thing(const char*).
The second one is a bit more complex. It essentially does the following
Create an object of...
How to allow to accept only image files?
...turn;
}
// here you can do whatever you want with your image. Now you are sure that it is an image
}
}
Encoding as Base64 in Java
...read why you shouldn't use sun.* packages.
Update (2016-12-16)
You can now use java.util.Base64 with Java 8. First, import it as you normally do:
import java.util.Base64;
Then use the Base64 static methods as follows:
byte[] encodedBytes = Base64.getEncoder().encode("Test".getBytes());
Syst...
Principal component analysis in Python
...o 90 %, 95 % ...
p.npc: number of principal components,
e.g. 2 if the top 2 eigenvalues are >= `fraction` of the total.
It's ok to change this; methods use the current value.
Methods:
The methods of class PCA transform vectors or arrays of e.g.
20 variables, 2 princip...