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Add custom messages in assert?

...rk; they’re compile-time constants and their use in this context is trivially optimized away. There is no runtime cost. – zneak Aug 9 '19 at 8:46 ...
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how to detect search engine bots with php?

...ming to them. It also depends on utility. I wouldn't use this to strip out all CSS, but I would use this to not store cookies, ignore location logging, or skip a landing page. – JonShipman Mar 26 '15 at 21:28 ...
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What is the difference between a field and a property?

...sed via get and set properties. Properties provide a level of abstraction allowing you to change the fields while not affecting the external way they are accessed by the things that use your class. public class MyClass { // this is a field. It is private to your class and stores the actual da...
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Finding quaternion representing the rotation from one vector to another

... Be aware that this does not handle the case of parallel vectors (both in the same direction or pointing in opposite directions). crossproduct will not be valid in these cases, so you first need to check dot(v1, v2) > 0.999999 and dot(v1, v2) < -0.999999, respectively, ...
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How to drop all tables in a SQL Server database?

...y tables. I found that code that works and does everything you try (delete all tables from your database): DECLARE @Sql NVARCHAR(500) DECLARE @Cursor CURSOR SET @Cursor = CURSOR FAST_FORWARD FOR SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.C...
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Is gcc's __attribute__((packed)) / #pragma pack unsafe?

... Yes, __attribute__((packed)) is potentially unsafe on some systems. The symptom probably won't show up on an x86, which just makes the problem more insidious; testing on x86 systems won't reveal the problem. (On the x86, misaligned accesses are handled in hardwa...
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How do I expire a PHP session after 30 minutes?

...ms with filesystems where atime tracking is not available. So it additionally might occur that a session data file is deleted while the session itself is still considered as valid because the session data was not updated recently. And second: session.cookie_lifetime session.cookie_lifetime ...
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What are some uses of template template parameters?

...alue) { } Here, H is a template, but I wanted this function to deal with all specializations of H. NOTE: I've been programming c++ for many years and have only needed this once. I find that it is a rarely needed feature (of course handy when you need it!). I've been trying to think of good examp...
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Why does running the Flask dev server run itself twice?

...g is the library that supplies Flask with the development server when you call app.run(). See the restart_with_reloader() function code; your script is run again with subprocess.call(). If you set use_reloader to False you'll see the behaviour go away, but then you also lose the reloading function...
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Cannot kill Python script with Ctrl-C

...you can't do anything with it after it exits. The process will finish when all non-daemon threads have finished; parent-child relationships don't come into that. – Thomas K Dec 6 '13 at 22:22 ...