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Check that an email address is valid on iOS [duplicate]
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return [emailTest evaluateWithObject:self];
}
@end
And then utilize:
if([@"emailString@email.com" isValidEmail]) { /* True */ }
if([@"InvalidEmail@notreallyemailbecausenosuffix" isValidEmail]) { /* False */ }
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django admin - add custom form fields that are not part of the model
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If for some reason, you get an AttributeError: Unable to lookup "extra_field"..., try adding a label to the extra_field definition. It seems that django tries to "guess" the label for it, by looking at the Model and the Model...
Any way to delete in vim without overwriting your last yank? [duplicate]
...in the registers:
"_dd
See also :help registers.
It's probably safest, if you want to paste something over and over again, to yank it into a "named" register.
"aY
Yanks a line into the a register. Paste it with "ap.
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Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
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See the C FAQ, Question 1.32
Q: What is the difference between these initializations?
char a[] = "string literal";
char *p = "string literal";
My program crashes if I try to assign a new value to p[i].
A: A string literal (the formal term
for a double-quot...
Add a new item to a dictionary in Python [duplicate]
...ther possible solution:
default_data.update({'item3': 3})
which is nice if you want to insert multiple items at once.
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How to encrypt/decrypt data in php?
...= openssl_random_pseudo_bytes($key_size, $strong);
// $strong will be true if the key is crypto safe
This can be done once or multiple times (if you wish to create a chain of encryption keys). Keep these as private as possible.
IV
The initialisation vector adds randomness to the encryption and r...
How do I install from a local cache with pip?
... downloaded and added to the PIP_DOWNLOAD_CACHE directory. For instance, I now have quite a few Django packages.
This doesn't remove the need for network access, as stated in the pip news, so it's not the answer for creating new virtualenvs on the airplane, but it's still great.
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Matplotlib: “Unknown projection '3d'” error
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First off, I think mplot3D worked a bit differently in matplotlib version 0.99 than it does in the current version of matplotlib.
Which version are you using? (Try running: python -c 'import matplotlib; print matplotlib."__version__")
I'm guessing you're running v...
Insert HTML with React Variable Statements (JSX)
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How does this work if you need to add something to <head>?
– Danielle Madeley
Oct 30 '15 at 3:37
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C++ convert hex string to signed integer
...dard, there are a few new utility functions which you can make use of! specifically, there is a family of "string to number" functions (http://en.cppreference.com/w/cpp/string/basic_string/stol and http://en.cppreference.com/w/cpp/string/basic_string/stoul). These are essentially thin wrappers aroun...