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How do you test that a Python function throws an exception?

...Case.assertRaises (or TestCase.failUnlessRaises) from the unittest module, for example: import mymod class MyTestCase(unittest.TestCase): def test1(self): self.assertRaises(SomeCoolException, mymod.myfunc) sha...
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Can I have onScrollListener for a ScrollView?

...) to it using the method addOnScrollChangedListener(). You can see more information about this class here. It lets you be aware of every scrolling event - but without the coordinates. You can get them by using getScrollY() or getScrollX() from within the listener though. scrollView.getViewTreeObs...
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HTML5 Email Validation

... In HTML5 you can do like this: <form> <input type="email" placeholder="Enter your email"> <input type="submit" value="Submit"> </form> And when the user press submit, it automatically shows an error message like: ...
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Detecting endianness programmatically in a C++ program

...t will often be warned against by compiler. That's exactly what unions are for ! bool is_big_endian(void) { union { uint32_t i; char c[4]; } bint = {0x01020304}; return bint.c[0] == 1; } The principle is equivalent to the type case as suggested by others, but this is...
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Check that an email address is valid on iOS [duplicate]

...rString : laxString; NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex]; return [emailTest evaluateWithObject:checkString]; } Discussion on Lax vs. Strict - http://blog.logichigh.com/2010/09/02/validating-an-e-mail-address/ And because categories are j...
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How do I execute inserts and updates in an Alembic upgrade script?

... What you are asking for is a data migration, as opposed to the schema migration that is most prevalent in the Alembic docs. This answer assumes you are using declarative (as opposed to class-Mapper-Table or core) to define your models. It shoul...
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How to obtain the number of CPUs/cores in Linux from the command line?

...will count the number of lines starting with "processor" in /proc/cpuinfo For systems with hyper-threading, you can use grep ^cpu\\scores /proc/cpuinfo | uniq | awk '{print $4}' which should return (for example) 8 (whereas the command above would return 16) ...
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c++ 写日志通用类,可设置日志级别 - C/C++ - 清泛网 - 专注C/C++及内核技术

...。代码经过较长时间的测试,可用性高。Logger.h #ifndef __LOGGER_H_ #define __LOGGER_H_ #include <iostream> #include <atlstr.h> #pragma warning(disable:4996) #define LEVEL_FATAL 0 #define LEVEL_ERROR 1 #define LEVEL_WARN 2 #define LEVEL_INFO 3 #define LEVEL_VERBOSE...
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How do I avoid capturing self in blocks when implementing an API?

...) and so the pair of objects will leak into the heap, occupying memory but forever unreachable without a debugger. Tragic, really. That case could be easily fixed by doing this instead: id progressDelegate = self.delegate; self.progressBlock = ^(CGFloat percentComplete) { [progressDelegate pro...
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How to get last items of a list in Python?

... You can use negative integers with the slicing operator for that. Here's an example using the python CLI interpreter: &gt;&gt;&gt; a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12] &gt;&gt;&gt; a [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12] &gt;&gt;&gt; a[-9:] [4, 5, 6, 7, 8, 9, 10, 11, 12]...