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ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type
...'Modified'. Before changing the state, the state is set to 'Detached' but calling Attach() does throw the same error. I'm using EF6.
...
Best way to merge two maps and sum the values of same key?
...mutable.Map[Int,Int] = Map(1 -> 109, 3 -> 300, 2 -> 20)
Specifically, the binary operator for Map[K, V] combines the keys of the maps, folding V's semigroup operator over any duplicate values. The standard semigroup for Int uses the addition operator, so you get the sum of values for eac...
Commonly accepted best practices around code organization in JavaScript [closed]
...ferent "namespaces" and sometimes individual classes in separate files. Usually I start with one file and as a class or namespace gets big enough to warrant it, I separate it out into its own file. Using a tool to combine all you files for production is an excellent idea as well.
...
Python argparse ignore unrecognised arguments
Optparse, the old version just ignores all unrecognised arguments and carries on. In most situations, this isn't ideal and was changed in argparse. But there are a few situations where you want to ignore any unrecognised arguments and parse the ones you've specified.
...
PHP abstract properties
...get_class($this) . ' must have a $tablename');
}
}
To enforce this for all derived classes of Foo_Abstract you would have to make Foo_Abstract's constructor final, preventing overriding.
You could declare an abstract getter instead:
abstract class Foo_Abstract {
abstract public function get_...
RegEx for Javascript to allow only alphanumeric
I need to find a reg ex that only allows alphanumeric. So far, everyone I try only works if the string is alphanumeric, meaning contains both a letter and a number. I just want one what would allow either and not require both.
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How to put multiple statements in one line?
...pproximate what you want.
As for the try ... except thing: It would be totally useless without the except. try says "I want to run this code, but it might throw an exception". If you don't care about the exception, leave away the try. But as soon as you put it in, you're saying "I want to handle a ...
What is the JavaScript convention for no operation?
... "function" // returns true
It can be invoked as a function and essentially does nothing as shown here:
setTimeout(function() {
console.log('Start: ', Date.now());
Function.prototype();
console.log('End : ', Date.now());
}, 1000);
Although this is a "true noop" since...
UIBarButtonItem with custom image and no border
...ation code here
}
@end
So anywhere in your code you can create bar item calling this method (provided that you include a header with its declaration).
P.S. You do not need to use 'v' UIView as you can create UIBarButtonItem with a button as custom view directly.
P.P.S. You also need [forward rel...
“Too many values to unpack” Exception
...nATupleWithThreeValues()
print a
print b
raises
Traceback (most recent call last):
File "c.py", line 3, in ?
a,b = returnATupleWithThreeValues()
ValueError: too many values to unpack
Now, the reason why this happens in your case, I don't know, but maybe this answer will point you in the r...