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“x not in y” or “not x in y”
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They always give the same result.
In fact, not 'ham' in 'spam and eggs' appears to be special cased to perform a single "not in" operation, rather than an "in" operation and then negating the result:
>>> import dis
>>> def notin():
'ham' not in 'spam and eggs'
&g...
How do I tell if a regular file does not exist in Bash?
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The test command ([ here) has a "not" logical operator which is the exclamation point (similar to many other languages). Try this:
if [ ! -f /tmp/foo.txt ]; then
echo "File not found!"
fi
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When to make a type non-movable in C++11?
...x objects. If std::mutex contained a native OS mutex type as a data member and the native type's address must stay fixed (because the OS maintains a list of pointers to its mutexes) then either std::mutex would have to store the native mutex type on the heap so it would stay at the same location whe...
How to validate phone numbers using regex
...ogether a comprehensive regex to validate phone numbers. Ideally it would handle international formats, but it must handle US formats, including the following:
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What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?
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Yes. They are different file formats (and their file extensions).
Wikipedia entries for each of the formats will give you quite a bit of information:
JPEG (or JPG, for the file extension; Joint Photographic Experts Group)
PNG (Portable Network Graphics)
BMP (B...
Use rvmrc or ruby-version file to set a project gemset with RVM?
I use RVM, the Ruby Version Manager to specify a Ruby version and a set of gems for each of my Rails projects.
5 Answers
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right click context menu for datagridview
... a datagridview in a .NET winform app. I would like to rightclick on a row and have a menu pop up. Then i would like to select things such as copy, validate, etc
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Protecting executable from reverse engineering?
I've been contemplating how to protect my C/C++ code from disassembly and reverse engineering. Normally I would never condone this behavior myself in my code; however the current protocol I've been working on must not ever be inspected or understandable, for the security of various people.
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Why Qt is misusing model/view terminology?
...ation page they state, that they simplified the MVC to MV by merging View and Controller and they are giving the following picture:
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What is the difference between a map and a dictionary?
... values. Isn't a dictionary the same? What is the difference between a map and a dictionary 1 ?
11 Answers
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