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How to validate an e-mail address in swift?
...z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
let emailPred = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
return emailPred.evaluate(with: email)
}
for versions of Swift earlier than 3.0:
func isValidEmail(email: String) -> Bool {
let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]...
std::function and std::bind: what are they, and when should they be used?
...
std::bind is for partial function application.
That is, suppose you have a function object f which takes 3 arguments:
f(a,b,c);
You want a new function object which only takes two arguments, defined as:
g(a,b) := f(a, 4, b);
g is a...
mongodb group values by multiple fields
For example, I have these documents:
3 Answers
3
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How to apply a function to two columns of Pandas dataframe
... Added an example to my answer, hope this does what you're looking for. If not, please provide a more specific example function since sum is solved successfully by any of the methods suggested so far.
– Aman
Nov 12 '12 at 14:51
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What is a clean, pythonic way to have multiple constructors in Python?
I can't find a definitive answer for this. As far as I know, you can't have multiple __init__ functions in a Python class. So how do I solve this problem?
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What is __future__ in Python used for and how/when to use it, and how it works
...uently appears in Python modules. I do not understand what __future__ is for and how/when to use it even after reading the Python's __future__ doc .
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TypeError: module.__init__() takes at most 2 arguments (3 given)
... you try it and find out. Python's great cos it has the interpreter. Great for quick experimentation
– Sheena
Jan 27 '17 at 5:10
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Can a dictionary be passed to django models on create?
...lled MyModel:
# create instance of model
m = MyModel(**data_dict)
# don't forget to save to database!
m.save()
As for your second question, the dictionary has to be the final argument. Again, extra and extra2 should be fields in the model.
m2 =MyModel(extra='hello', extra2='world', **data_dict)
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What's the UIScrollView contentInset property for?
... to me what the contentInset property in a UIScrollView instance is used for? And maybe provide an example?
5 Answers
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std::vector performance regression when enabling C++11
I have found an interesting performance regression in a small C++ snippet, when I enable C++11:
1 Answer
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