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Good examples of Not a Functor/Functor/Applicative/Monad?
...tructor which is not a Functor:
newtype T a = T (a -> Int)
You can make a contravariant functor out of it, but not a (covariant) functor. Try writing fmap and you'll fail. Note that the contravariant functor version is reversed:
fmap :: Functor f => (a -> b) -> f a ->...
Sample random rows in dataframe
...d the appropriate function that would return a specified number of rows picked up randomly without replacement from a data frame in R language? Can anyone help me out?
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Accessing dict_keys element by index in Python3
I'm trying to access a dict_key's element by its index:
6 Answers
6
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What is the difference between const and readonly in C#?
...in code. When this is compiled,
in the case of the const value, it is like a find-replace, the value 2 is 'baked into' the AssemblyB's IL. This means that if tomorrow I'll update I_CONST_VALUE to 20 in the future. AssemblyB would still have 2 till I recompile it.
in the case of the readonly value...
Show a Form without stealing focus?
...ivation
{
get { return true; }
}
And if you don't want the user to click this notification window either, you can override CreateParams:
protected override CreateParams CreateParams
{
get
{
CreateParams baseParams = base.CreateParams;
const int WS_EX_NOACTIVATE = 0x08000000;
co...
How to remove all .svn directories from my application directories
...o clean all .svn directories from my application directory tree. I am looking for a recursive command in the Linux shell that will traverse the entire tree and delete the .svn files.
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Getting the index of the returned max or min item using max()/min() on a list
...dex of the value returned by max() or min() . In other words, I need to know which move produced the max (at a first player's turn) or min (second player) value.
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Installing vim with ruby support (+ruby)
...
Some package provides vim-ruby on Ubuntu, for example vim-nox.
simply:
sudo apt-get install vim-nox;
will get you vim with ruby, as well as compiled in "support for scripting with Perl, Python, Ruby, and TCL but no GUI."
sudo ap...
How to run a single RSpec test?
...d then add a focus tag to the it, context or describe to run only that block:
it 'runs a test', :focus do
...test code
end
RSpec documentation:
https://www.rubydoc.info/github/rspec/rspec-core/RSpec/Core/Configuration#filter_run_when_matching-instance_method
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DbEntityValidationException - How can I easily tell what caused the error?
I have a project that uses Entity Framework. While calling SaveChanges on my DbContext , I get the following exception:
...