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How to “test” NoneType in python?
...ariable has None in it or not.
Quoting from is docs,
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object. x is not y yields the inverse truth value.
Since there can be only one instance of None, is would be the preferred way to check...
Check if a string matches a regex in Bash script
...=~ ^regex$ ]] && echo "matched" || echo "did not match"
where commands after && are executed if the test is successful, and commands after || are executed if the test is unsuccessful.
Note this is based on the solution by Aleks-Daniel Jakimenko in User input date format verification...
Best way to represent a Grid or Table in AngularJS with Bootstrap 3? [closed]
I am creating an App with AngularJS and Bootstrap 3. I want to show a table/grid with thousands of rows. What is the best available control for AngularJS & Bootstrap with features like Sorting, Searching, Pagination etc.
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Clojure differences between Ref, Var, Agent, Atom, with examples
...here to use Ref, Var, Agent, Atom. I read book, but, still couldn't understand the real world examples.
5 Answers
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Why are there two kinds of functions in Elixir?
I'm learning Elixir and wonder why it has two types of function definitions:
8 Answers
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C# using streams
...treams are kind of mysterious to me. I don't know when to use which stream and how to use them. Can someone explain to me how streams are used?
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Why can't an anonymous method be assigned to var?
...to be the default instead of Predicate or Action or any other possibility? And, for lambdas, why is it obvious that the intention is to choose the delegate form, rather than the expression tree form?
But we could say that Func is special, and that the inferred type of a lambda or anonymous method i...
lose vim colorscheme in tmux mode
I'm running iterm2 and when I'm in tmux mode the colorscheme I have set in vim does not show up. Only the color scheme I've set in iterm. If I run vim from shell the colorscheme appears correct - its only when I'm in tmux mode.
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sys.argv[1] meaning in script
I'm currently teaching myself Python and was just wondering (In reference to my example below) in simplified terms what the sys.argv[1] represents. Is it simply asking for an input?
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Why can't I use float value as a template parameter?
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The current C++ standard does not allow float (i.e. real number) or character string literals to be used as template non-type parameters. You can of course use the float and char * types as normal arguments.
Perhaps the author is using a com...