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Is there a simple, elegant way to define singletons? [duplicate]
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I don't really see the need, as a module with functions (and not a class) would serve well as a singleton. All its variables would be bound to the module, which could not be instantiated repeatedly anyway.
If you do wish to use a cla...
Should I use scipy.pi, numpy.pi, or math.pi?
...gt;> math.pi == np.pi == scipy.pi
True
So it doesn't matter, they are all the same value.
The only reason all three modules provide a pi value is so if you are using just one of the three modules, you can conveniently have access to pi without having to import another module. They're not provi...
What is a sealed trait?
...ut also part of a restricted (sealed ?) context where makes sense to check all possible subtypes like yes | no , even | odd etc...
– Mário de Sá Vera
Apr 7 '18 at 16:13
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CSS :after not adding content to certain elements
...t;button>, <textarea>,
<input>, and <select> tags). All other elements types can be referred
to as non-replaced elements.
:before and :after only work with non-replaced elements.
From the spec:
Note. This specification does not fully define the interaction of
:befor...
What does the * * CSS selector do?
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just one more thing to ask--is it really relevant to use * * ? as although I grasp the concept but not getting it in practical terms :(
– swapnesh
Mar 25 '13 at 5:06
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Host 'xxx.xx.xxx.xxx' is not allowed to connect to this MySQL server
...CREATE USER 'monty'@'localhost' IDENTIFIED BY 'some_pass';
mysql> GRANT ALL PRIVILEGES ON *.* TO 'monty'@'localhost'
-> WITH GRANT OPTION;
mysql> CREATE USER 'monty'@'%' IDENTIFIED BY 'some_pass';
mysql> GRANT ALL PRIVILEGES ON *.* TO 'monty'@'%'
-> WITH GRANT OPTION;
...
Why always ./configure; make; make install; as 3 separate steps?
...guration. Also ./configure checks for missing libraries that should be installed. Anything wrong here causes not to build your application. That's why distros have packages that are installed on different places, because every distro thinks it's better to install certain libraries and files to certa...
SQL query for finding records where count > 1
... a user ID, an account number, a ZIP code and a date. I would like to find all records for all users that have more than one payment per day with the same account number.
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Haskell testing workflow
... picking the right tools.
test-framework provides a one-stop shop to run all your HUnit test-cases and QuickCheck properties all from one harness.
Code coverage is built into GHC in the form of the HPC tool.
Criterion provides some pretty great benchmarking machinery
I'll use as a running exampl...
Create a submodule repository from a folder and keep its git commit history
...ommit it
git filter-branch --subdirectory-filter <directory 1> -- --all
You should now have a git repository with the files from directory 1 in your repo's root with all related commit history.
Step 4
Create your online repository and push your new repository!
git remote add origin <...