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PHP global in functions

...ngletons, registries, constants). You do not want to use them. A function call should not have to rely on anything outside, e.g. function fn() { global $foo; // never ever use that $a = SOME_CONSTANT // do not use that $b = Foo::SOME_CONSTANT; // do not use that unl...
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What is the difference between an interface and abstract class?

...'t do anything. It's just a pattern. For example (pseudo code): // I say all motor vehicles should look like this: interface MotorVehicle { void run(); int getFuel(); } // My team mate complies and writes vehicle looking that way class Car implements MotorVehicle { int fuel; vo...
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What is the difference between “ is None ” and “ ==None ”

... class Foo: def __eq__(self,other): return True foo=Foo() print(foo==None) # True print(foo is None) # False share | improve thi...
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Passing references to pointers in C++

As far as I can tell, there's no reason I shouldn't be allowed to pass a reference to a pointer in C++. However, my attempts to do so are failing, and I have no idea why. ...
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SQLite - UPSERT *not* INSERT or REPLACE

...e columns in the table: ID, NAME, ROLE BAD: This will insert or replace all columns with new values for ID=1: INSERT OR REPLACE INTO Employee (id, name, role) VALUES (1, 'John Foo', 'CEO'); BAD: This will insert or replace 2 of the columns... the NAME column will be set to NULL or the def...
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Partial Commits with Subversion

...sing the full GIT feature set (including partial commits) and then push it all back to the SVN repository. git-svn (1) share | improve this answer | follow | ...
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Select random row from a sqlite table

... the day seeded with unix epoc for today at noon so it shows the same book all day even if the query is run multiple times. Yes I know caching is more efficient for this use case just an example. – danielson317 Apr 22 at 17:18 ...
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How to write LaTeX in IPython Notebook?

...you would. Then use nbconvert to turn the ipynb to TeX (code, figures and all), and run latex to render that to PDF, etc. You don't get live-rendered TeX in the browser like you do with MathJax / Markdown, but you do still have TeX / code in one document. – minrk ...
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How do I remove code duplication between similar const and non-const member functions?

... C &>(*this).get()); } char c; }; The two casts and function call may be ugly but it's correct. Meyers has a thorough explanation why. share | improve this answer | ...
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How to use a class from one C# project with another C# project

...that you wish to access directly must have a sufficient access level: typically this means they must be made public. share | improve this answer | follow | ...