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Saving an Object (Data persistence)

...ics. cPickle (or _pickle) vs pickle It's almost always preferable to actually use the cPickle module rather than pickle because the former is written in C and is much faster. There are some subtle differences between them, but in most situations they're equivalent and the C version will provide gr...
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Is there a performance difference between a for loop and a for-each loop?

... iterator or index variable completely. The resulting idiom applies equally to collections and arrays: // The preferred idiom for iterating over collections and arrays for (Element e : elements) { doSomething(e); } When you see the colon (:), read it as “in.” Thus, the loop ab...
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Python __str__ versus __unicode__

...onfusing, but in 2.x we're stuck with them for compatibility reasons. Generally, you should put all your string formatting in __unicode__(), and create a stub __str__() method: def __str__(self): return unicode(self).encode('utf-8') In 3.0, str contains characters, so the same methods are nam...
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grid controls for ASP.NET MVC? [closed]

...olumns (I find myself adding some touch as rowspans, graphics, etc to some tables to make them nicer) – Eduardo Molteni Sep 17 '11 at 17:22 ...
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Is there a TRY CATCH command in Bash

... writing a shell script and need to check that a terminal app has been installed. I want to use a TRY/CATCH command to do this unless there is a neater way. ...
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How to filter multiple values (OR operation) in angularJS

...ntion but your example doesn't seem to work as expected. The output in the table seems rather inconsistent. – Hultner Sep 16 '14 at 14:01 ...
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Placeholder in UITextView

... I made a few minor modifications to bcd's solution to allow for initialization from a Xib file, text wrapping, and to maintain background color. Hopefully it will save others the trouble. UIPlaceHolderTextView.h: #import <Foundation/Foundation.h> IB_DESIGNABLE @interfac...
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How update the _id of one MongoDB Document?

I want update an _id field of one document. I know it's not a really good pratice. But with some technical reason, I need update it. If I try to update it I get: ...
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Does using “new” on a struct allocate it on the heap or stack?

...hen you create an instance of a class with the new operator, memory gets allocated on the heap. When you create an instance of a struct with the new operator where does the memory get allocated, on the heap or on the stack ? ...
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What is a clean, pythonic way to have multiple constructors in Python?

... Actually None is much better for "magic" values: class Cheese(): def __init__(self, num_holes = None): if num_holes is None: ... Now if you want complete freedom of adding more parameters: class Cheese...