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How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
retrieve links from web page using python and BeautifulSoup [closed]
...ref'):
print(link['href'])
The BeautifulSoup documentation is actually quite good, and covers a number of typical scenarios:
https://www.crummy.com/software/BeautifulSoup/bs4/doc/
Edit: Note that I used the SoupStrainer class because it's a bit more efficient (memory and speed wise), if you...
Creating your own header file in C
... I was wondering if you could elaborate on how to compile with all required files and not have to include foo.c into gcc program argument. What is this technique called or what program can accomplish this outside of IDE - Make comes to my mind
– nf071590
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Combining two expressions (Expression)
...m);
}
Starting from .NET 4.0, there is the ExpressionVisitor class which allows you to build expressions that are EF safe.
public static Expression<Func<T, bool>> AndAlso<T>(
this Expression<Func<T, bool>> expr1,
Expression<Func<T, bool>&...
Why would introducing useless MOV instructions speed up a tight loop in x86_64 assembly?
... in the branch prediction table
moving the branch eliminated the alias and allowed the branch to be predicted correctly
Your Core2 doesn't keep a separate history record for each conditional jump. Instead it keeps a shared history of all conditional jumps. One disadvantage of global branch predic...
Could not locate Gemfile
...application on my server using Ruby, Gems, and Bundler. I am trying to install another Ruby on under a different user account but on the same VPS. When I go to run
...
Which characters make a URL invalid?
...
@techiferous, Yeah, I forgot to allow "%" escaped characters. It should've looked more like: /^([!#$&-;=?-[]_a-z~]|%[0-9a-fA-F]{2})+$/ Was there anything else that you found it should've been accepting? (Just to be clear, that regex only checks ...
Easy pretty printing of floats in python?
...
It's an old question but I'd add something potentially useful:
I know you wrote your example in raw Python lists, but if you decide to use numpy arrays instead (which would be perfectly legit in your example, because you seem to be dealing with arrays of numbers), there is ...
pytest: assert almost equal
...
I noticed that this question specifically asked about py.test. py.test 3.0 includes an approx() function (well, really class) that is very useful for this purpose.
import pytest
assert 2.2 == pytest.approx(2.3)
# fails, default is ± 2.3e-06
assert 2.2 == pyte...
Unittest setUp/tearDown for several tests
...ably going to be to create your own derived TestSuite and override run(). All other calls would be handled by the parent, and run would call your setup and teardown code around a call up to the parent's run method.
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