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Check if something is (not) in a list in Python
... @nightcracker That makes no sense as A not in B is reduced to doing not B.__contains__(A) which is the same as what not A in B is reduced to which is not B.__contains__(A).
– Dan D.
May 2 '12 at 0:33
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In Python, what is the difference between “.append()” and “+= []”?
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In general case append will add one item to the list, while += will copy all elements of right-hand-side list into the left-hand-side list.
Update: perf analysis
Comparing bytecodes we can assume that append version wastes cycles in LOAD_ATTR + CALL_FUNCTION, and += version -- in BUILD_LIST. App...
private[this] vs private
...rotected over public doesn't apply.
Use private[this] where performance really matters (since you'll get direct field access instead of methods this way). Otherwise, just settle on one style so people don't need to figure out why this property is private and that one is private[this].
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snprintf and Visual Studio 2010
... the expected behavior for snprintf:
int snprintf( char* buffer, std::size_t buf_size, const char* format, ... );
Writes at most buf_size - 1 characters to a buffer. The resulting
character string will be terminated with a null character, unless
buf_size is zero. If buf_size is zero, nothi...
Piping command output to tee but also save exit code of command [duplicate]
I have a shell script in which I wrap a command (mvn clean install), to redirect the output to a logfile.
4 Answers
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Hidden Features of Xcode
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It's called "option" on the Mac, not "alt". And if you want fancy symbols, it can be written ⌥⌘↑
– Brian Campbell
Mar 31 '09 at 15:33
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What are conventions for filenames in Go?
...he go test tool.
Files with os and architecture specific suffixes automatically follow those same constraints, e.g. name_linux.go will only build on linux, name_amd64.go will only build on amd64. This is the same as having a //+build amd64 line at the top of the file
See the docs for the go build...
serve current directory from command line
...also running on a Mac. Tried it with Ruby 1.8.7, 1.9.3 and 2.0.0, and they all work. Weird.
– Daniel Perez Alvarez
Sep 9 '13 at 9:04
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WARN Could not determine content-length of response body. Set content-length of the response or set
I just upgraded to rails 3.2.2, and now on rails s, page load, I get all these errors in the log:
3 Answers
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How to flatten tree via LINQ?
...lt;T>> f
) => e.SelectMany(c => f(c).Flatten(f)).Concat(e);
Call this function like this:
IEnumerable<MyNode> tree = ....
var res = tree.Flatten(node => node.Elements);
If you would prefer flattening in pre-order rather than in post-order, switch around the sides of the Con...