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How to get rid of the 'undeclared selector' warning
I want to use a selector on an NSObject instance without the need for an implemented protocol. For example, there's a category method that should set an error property if the NSObject instance it's called on supports it. This is the code, and the code works as intended:
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What's the difference between eval, exec, and compile?
...on, and exec is used to execute dynamically generated Python code only for its side effects.
eval and exec have these two differences:
eval accepts only a single expression, exec can take a code block that has Python statements: loops, try: except:, class and function/method definitions and so on...
How to get the pure text without HTML element using JavaScript?
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[2017-07-25] since this continues to be the accepted answer, despite being a very hacky solution, I'm incorporating Gabi's code into it, leaving my own to serve as a bad example.
<style>
.A {background: blue;}
.B {font-style: italic;}
.C {font-weight: bold;}
</style>
<scri...
Why are Where and Select outperforming just Select?
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Select iterates once over the entire set and, for each item, performs a conditional branch (checking for validity) and a + operation.
Where+Select creates an iterator that skips invalid elements (doesn't yield them), performing a +...
Constants in Objective-C
...Constants.m should be added to your application/framework's target so that it is linked in to the final product.
The advantage of using string constants instead of #define'd constants is that you can test for equality using pointer comparison (stringInstance == MyFirstConstant) which is much faster...
What does numpy.random.seed(0) do?
What does np.random.seed do in the below code from a Scikit-Learn tutorial? I'm not very familiar with NumPy's random state generator stuff, so I'd really appreciate a layman's terms explanation of this.
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How to implement the --verbose or -v option into a script?
... than putting the if in the function, which you might be tempted to do, do it like this:
if verbose:
def verboseprint(*args):
# Print each argument separately so caller doesn't need to
# stuff everything to be printed into a single string
for arg in args:
prin...
Is Safari on iOS 6 caching $.ajax results?
...aching $.ajax calls. This is in the context of a PhoneGap application so it is using the Safari WebView. Our $.ajax calls are POST methods and we have cache set to false {cache:false} , but still this is happening. We tried manually adding a TimeStamp to the headers but it did not help.
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How do I use su to execute the rest of the bash script as that user?
I've written a script that takes, as an argument, a string that is a concatenation of a username and a project. The script is supposed to switch (su) to the username, cd to a specific directory based upon the project string.
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How to use the “number_to_currency” helper method in the model rather than view?
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It’s not available because its use in a model (typically) violates MVC (and it does seem to in your case). You're taking data and manipulating it for presentation. This, by definition, belongs in the view, not the model.
H...