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How do I get the currently displayed fragment?

...tManager().getBackStackEntryCount() == 0) { return null; } String tag = getSupportFragmentManager().getBackStackEntryAt(getSupportFragmentManager().getBackStackEntryCount() - 1).getName(); return (BaseFragment) getSupportFragmentManager().findFragmentByTag(tag); } ...
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Which characters are valid/invalid in a JSON key name?

...here any forbidden characters in key names, for JavaScript objects or JSON strings? Or characters that need to be escaped? ...
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Should import statements always be at the top of a module?

...t that's only paid once. Putting the imports within a function will cause calls to that function to take longer. So if you care about efficiency, put the imports at the top. Only move them into a function if your profiling shows that would help (you did profile to see where best to improve perform...
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What do *args and **kwargs mean? [duplicate]

...r **kwargs as the last items in your function definition’s argument list allows that function to accept an arbitrary number of arguments and/or keyword arguments. For example, if you wanted to write a function that returned the sum of all its arguments, no matter how many you supply, you could wr...
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What's the state of the art in email validation for Rails?

...del: class TestUser include Mongoid::Document field :email, type: String validates :email, email: true end Your validator (goes in app/validators/email_validator.rb) class EmailValidator < ActiveModel::EachValidator EMAIL_ADDRESS_QTEXT = Regexp.new '[^\\x0d\\x22\\x5c\\x8...
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'typeid' versus 'typeof' in C++

... a type name, not just an expression. You can say typeid(5) or typeid(std::string) if you want. – Rob Kennedy Dec 31 '09 at 19:25 1 ...
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How to access the ith column of a NumPy multidimensional array?

...nswered Apr 20 '13 at 14:05 AkavallAkavall 62.1k3838 gold badges170170 silver badges215215 bronze badges ...
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Transpose/Unzip Function (inverse of zip)?

...'d', 4)]) [('a', 'b', 'c', 'd'), (1, 2, 3, 4)] The way this works is by calling zip with the arguments: zip(('a', 1), ('b', 2), ('c', 3), ('d', 4)) … except the arguments are passed to zip directly (after being converted to a tuple), so there's no need to worry about the number of arguments g...
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Markdown and including multiple files

Is there any markdown fork that allows you to reference other files, something like an includes file? Specifically, I want to create a separate markdown file with links that I call often but not always (call this B.md), then when I link by reference in the md file I'm writing (A.md), I'd like it to ...
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Crontab Day of the Week syntax

... @Nikita check for typos or extra spaces. I have both a "Mon-Fri" and a "Thu" in my crontab on Ubuntu 14.04.3 and both work just fine. I suspect if there's a space between any of the characters, you'd end up with an error. – Dale A...