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Single Line Nested For Loops
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The best source of information is the official Python tutorial on list comprehensions. List comprehensions are nearly the same as for loops (certainly any list comprehension can be written as a for-loop) but they are often faster than using a for loop.
Look at this longer list comprehension fr...
There is already an open DataReader associated with this Command which must be closed first
... not clear from your example where this happens because the example is not complete.
One thing that can cause this is lazy loading triggered when iterating over the results of some query.
This can be easily solved by allowing MARS in your connection string. Add MultipleActiveResultSets=true to the...
What does “#define _GNU_SOURCE” imply?
...OSIX-specified functions, where the GNU folks disagreed with the standards committee on how the functions should behave and decided to do their own thing.
As long as you're aware of these things, it should not be a problem to define _GNU_SOURCE, but you should avoid defining it and instead define ...
Python constructors and __init__
... Wikipedia is a good starting point. For Python-specific stuff, I highly recommend the Python docs.
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Select columns from result set of stored procedure
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This was interesting: sqlnerd.blogspot.com/2005/09/…
– d-_-b
Mar 4 '12 at 23:40
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Are there any free Xml Diff/Merge tools available? [closed]
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KDiff3 is not XML specific, but it is free. It does a nice job of comparing and merging text files.
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When I catch an exception, how do I get the type, file, and line number?
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Position a CSS background image x pixels from the right?
...ition: right 30px center;
It works in most browsers. See: http://caniuse.com/#feat=css-background-offsets for full list.
More information: http://www.w3.org/TR/css3-background/#the-background-position
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Copy entire contents of a directory to another using php
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