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How to convert an enum type variable to a string?
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@AdN That design is wrong. The mapping from enum to human-readable string shouldn't be implemented as an array of strings indexed by the enum value. Your experience (presumably) shows why. The mapping should be an explitiy array of (enum,string) pairs, so if you f...
'const string' vs. 'static readonly string' in C#
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+1, And the obvious conclusion, from a practical and semantic point-of-view: const should only be used for constants - constants being values that never, ever, ever change.
– LukeH
Jul 6 '10 at 23:49
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How to create a new database using SQLAlchemy?
...eries in a transaction. To get around this, get the underlying connection from the engine:
>>> conn = engine.connect()
But the connection will still be inside a transaction, so you have to end the open transaction with a commit:
>>> conn.execute("commit")
And you can then pr...
When to use pip requirements file versus install_requires in setup.py?
...quirements file).
So, in summary: install_requires is to keep people away from things that you know don't work, while requirements files to lead people towards things you know do work. One reason for this is that install_requires requirements are always checked, and cannot be disabled without actu...
Php multiple delimiters in explode
... I found having the spaces in between the / ( and ) / stopped preg_split from working. I had to remove the spaces and then it worked as expected (using PHP 7)
– Boardy
Mar 11 '18 at 0:31
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find() with nil when there are no records
... A reason to use this rather than find_by_id is that it's portable from Rails 3 to 4. In rails 4, it's find_by(:id => 10).
– Gene
Jun 9 '14 at 23:42
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Using Predicate in Swift
...". That is not correct. That uses string interpolation, which is different from predicate formatting and will generally not work for this.)
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How do I parse an ISO 8601-formatted date?
...ou're using Python 3.7, have a look at this answer about datetime.datetime.fromisoformat.
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What are some (concrete) use-cases for metaclasses?
... This is true for Python 3 as well, because a class B, inheriting from A, whose metaclass is M, is also a type-of M. So, when B is evaluated, M is invoked to create it, and this effectively allows you to "work on any subclasses" (of A). Having said that, Python 3.6 introduced the much simpl...
do you have kcachegrind like profiling tools for mac [closed]
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from this, blog.josephscott.org/2013/07/03/… in comments, to get around system protection to use dot: from @Motrin: This does no longer work in OSX El Capitan due to System Integration Protection: sudo ln -s /usr/local/bin...