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How should I read a file line-by-line in Python?
...e.txt') as fp:
for line in fp:
print line
We are all spoiled by CPython's relatively deterministic reference-counting scheme for garbage collection. Other, hypothetical implementations of Python will not necessarily close the file "quickly enough" without the with block if they use so...
smart pointers (boost) explained
...object after it goes out of scope.
Share of ownership can be implemented by having a copy constructor. This naturally copies a smart pointer and both the copy and the original will reference the same object. Transfer of ownership cannot really be implemented in C++ currently, because there are no ...
What is a plain English explanation of “Big O” notation?
...(2n) becomes insignificant (accounting for 0.0002% of the total operations by that stage).
One can notice that we've assumed the worst case scenario here. While multiplying 6 digit numbers, if one of them has 4 digits and the other one has 6 digits, then we only have 24 multiplications. Still, we ca...
Why can't you modify the data returned by a Mongoose Query (ex: findById)
When I try to change any part of the data returned by a Mongoose Query it has no effect.
2 Answers
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'setInterval' vs 'setTimeout' [duplicate]
...he interval is reached. It should not be nested into its callback function by the script author to make it loop, since it loops by default. It will keep firing at the interval unless you call clearInterval().
if you want to loop code for animations or clocks
Then use setInterval.
function doStuff(...
What techniques can be used to speed up C++ compilation times?
...standard headers don't have a respective declarations header.
Prefer pass-by-reference to pass-by-value in function signatures. This will eliminate the need to #include the respective type definitions in the header file and you will only need to forward-declare the type. Of course, prefer const ref...
In Visual Studio C++, what are the memory allocation representations?
...p://en.wikipedia.org/wiki/Magic_number_(programming)
* 0xABABABAB : Used by Microsoft's HeapAlloc() to mark "no man's land" guard bytes after allocated heap memory
* 0xABADCAFE : A startup to this value to initialize all free memory to catch errant pointers
* 0xBAADF00D : Used by Microsoft's Local...
brew update: The following untracked working tree files would be overwritten by merge:
...po, you have to update or reset brew to the master branch version. brew [by default] is located in the /usr/local folder, so you
Go to that folder [first command] which also should update permissions (if not see below)
Fetch the origin [second command] which means to update your LOCAL version ...
How to get last N records with activerecord?
...
Updated Answer (2020)
You can get last N records simply by using last method:
Record.last(N)
Example:
User.last(5)
Returns 5 users in descending order by their id.
Deprecated (Old Answer)
An active record query like this I think would get you what you want ('Something' is the mode...
Why are functions in Ocaml/F# not recursive by default?
...s it that functions in F# and Ocaml (and possibly other languages) are not by default recursive?
6 Answers
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