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Split by comma and strip whitespace in Python

... Use list comprehension -- simpler, and just as easy to read as a for loop. my_string = "blah, lots , of , spaces, here " result = [x.strip() for x in my_string.split(',')] # result is ["blah", "lots", "of", "spaces", "here"] See: Python docs on List Comp...
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Create a CSV File for a user in PHP

...re important. To ensure good display, put doublequotes around your fields, and don't forget to replace double-quotes inside fields to double double-quotes: `echo '"'.str_replace('"','""',$record1).'","'.str_replace.... – Mala Jul 1 '10 at 21:21 ...
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how to listen to N channels? (dynamic select statement)

...cks until at least one of the cases can proceed, makes a uniform pseudo-random choice, and then executes that case. It returns the index of the chosen case and, if that case was a receive operation, the value received and a boolean indicating whether the value corresponds to a send on the ch...
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Implementing Fast and Efficient Core Data Import on iOS 5

... sense having that MOC wait until the end to save. It has its own thread, and it will help keep memory down as well. You wrote: Then at the end of the import process, I save on the master/parent context which, ostensibly, pushes modifications out to the other child contexts including the m...
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CSS Display an Image Resized and Cropped

I want to show an image from an URL with a certain width and height even if it has a different size ratio. So I want to resize (maintaining the ratio) and then cut the image to the size I want. ...
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Storing DateTime (UTC) vs. storing DateTimeOffset

...ing from/to the database does DateTime conversion (from UTC to local time, and from local time to UTC), so I can use DateTime.Now (derivations and comparisions) throughout the system without worrying about time zones. ...
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When splitting an empty string in Python, why does split() return an empty list while split('\n') re

I am using split('\n') to get lines in one string, and found that ''.split() returns an empty list, [] , while ''.split('\n') returns [''] . Is there any specific reason for such a difference? ...
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Does async(launch::async) in C++11 make thread pools obsolete for avoiding expensive thread creation

...rong. I was under the impression that Linux thread creation was very cheap and after testing I determined that the overhead of function call in a new thread vs. a normal one is enormous. The overhead for creating a thread to handle a function call is something like 10000 or more times slower than a ...
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What does “fragment” mean in ANTLR?

...is somewhat akin to an inline function: It makes the grammar more readable and easier to maintain. A fragment will never be counted as a token, it only serves to simplify a grammar. Consider: NUMBER: DIGITS | OCTAL_DIGITS | HEX_DIGITS; fragment DIGITS: '1'..'9' '0'..'9'*; fragment OCTAL_DIGITS: '...
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What is the difference between native code, machine code and assembly code?

I'm confused about machine code and native code in the context of .NET languages. 4 Answers ...