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Check if all elements in a list are identical

... = next(iterator) except StopIteration: return True return all(first == rest for rest in iterator) One-liner: def checkEqual2(iterator): return len(set(iterator)) <= 1 Also one-liner: def checkEqual3(lst): return lst[1:] == lst[:-1] The difference between the 3 versi...
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The relationship could not be changed because one or more of the foreign-key properties is non-nulla

... You should delete old child items thisParent.ChildItems one by one manually. Entity Framework doesn't do that for you. It finally cannot decide what you want to do with the old child items - if you want to throw them away or if you want to keep and assign them to other parent entities. You must ...
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JavaScript and Threads

...onBat JavaScript Benchmark (first link) The Gears plugin can also be installed in Firefox. Safari 4, and the WebKit nightlies have worker threads: JavaScript Ray Tracer Chrome has Gears baked in, so it can do threads, although it requires a confirmation prompt from the user (and it uses a d...
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How to import module when module name has a '-' dash or hyphen in it?

...appens with sys.modules, you don't need it to import itself), just getting all of the file's globals into your own scope, you can use execfile # contents of foo-bar.py baz = 'quux' >>> execfile('foo-bar.py') >>> baz 'quux' >>> ...
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Java Reflection: How to get the name of a variable?

...they are in scope. Perhaps a byte-code engineering library like ASM would allow you to inspect this information at runtime. The only reasonable place I can think of for needing this information is in a development tool, and so byte-code engineering is likely to be useful for other purposes too. ...
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How do you echo a 4-digit Unicode character in Bash?

...d like to add the Unicode skull and crossbones to my shell prompt (specifically the 'SKULL AND CROSSBONES' (U+2620)), but I can't figure out the magic incantation to make echo spit it, or any other, 4-digit Unicode character. Two-digit one's are easy. For example, echo -e "\x55", . ...
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I want to get the type of a variable at runtime

...that comparison return true, but it would require a few book chapters to really cover TypeTag, so I'll stop here. Finally, maybe you don't care about the type of the variable at all. Maybe you just want to know what is the class of a value, in which case the answer is rather simple: val x = 5 x.ge...
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How to make good reproducible pandas examples

...s. Disclaimer: Writing a good question is HARD. The Good: do include small* example DataFrame, either as runnable code: In [1]: df = pd.DataFrame([[1, 2], [1, 3], [4, 6]], columns=['A', 'B']) or make it "copy and pasteable" using pd.read_clipboard(sep='\s\s+'), you can format the text for Sta...
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Python unit test with base and sub class

...test class CommonTests(object): def testCommon(self): print 'Calling BaseTest:testCommon' value = 5 self.assertEquals(value, 5) class SubTest1(unittest.TestCase, CommonTests): def testSub1(self): print 'Calling SubTest1:testSub1' sub = 3 sel...
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Getting started with Haskell

...'ve done this by reading tutorials and watching screencasts, but nothing really seems to stick. Now, in learning various imperative/OO languages (like C, Java, PHP), exercises have been a good way for me to go. But since I don't really know what Haskell is capable of and because there are many new c...