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When does invoking a member function on a null instance result in undefined behavior?
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Both (a) and (b) result in undefined behavior. It's always undefined behavior to call a member function through a null pointer. If the function is static, it's technically undefined as well, but there's some dispute.
The first thing to understand is why it's undefi...
How do I script a “yes” response for installing programs?
I work with Amazon Linux instances and I have a couple scripts to populate data and install all the programs I work with, but a couple of the programs ask:
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What does $$ (dollar dollar or double dollar) mean in PHP?
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A syntax such as $$variable is called Variable Variable.
For example, if you consider this portion of code :
$real_variable = 'test';
$name = 'real_variable';
echo $$name;
You will get the following output :
test
Here :
$real_variable contains test
$name contains the name o...
Should I use Java date and time classes or go with a 3rd party library like Joda Time?
...ting a web based system which will be used in countries from all over the world. One type of data which must be stored is dates and times.
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Best way to change the background color for an NSView
I'm looking for the best way to change the backgroundColor of an NSView . I'd also like to be able to set the appropriate alpha mask for the NSView . Something like:
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Stop LastPass filling out a form
...y to prevent the LastPass browser extension from filling out a HTML-based form with a input field with the name "username"?
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Is there an upside down caret character?
...arge number of classic ASP pages, many of which have tabular data with no sort capabilities at all. Whatever order the original developer used in the database query is what you're stuck with.
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Batch script to delete files
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I can't speak for the OP, but on my system there's no problem finding a path with %, and escaping with %% keeps the system from finding it.
– RonaldBarzell
Dec 7 '12 at 13:36
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Check that an email address is valid on iOS [duplicate]
...String : laxString;
NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];
return [emailTest evaluateWithObject:checkString];
}
Discussion on Lax vs. Strict - http://blog.logichigh.com/2010/09/02/validating-an-e-mail-address/
And because categories are ju...
How can I programmatically determine if my app is running in the iphone simulator?
As the question states, I would mainly like to know whether or not my code is running in the simulator, but would also be interested in knowing the specific iphone version that is running or being simulated.
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