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Lock-free multi-threading is for real threading experts
... Most of the classic lock-free structures (lists, queues, concurrent maps, etc) had no spinning even for shared mutable structures, and practical existing implementations of the same in, for example, Java follow the same pattern (I'm not as familiar with what's available in native-compiled C or C++ ...
Referring to the null object in Python
...nd is used to control and test special conditions (e.g. boundaries, state, etc.). Such a value is called a sentinel and it can be used the way None is used as a signal. It's trivial to create a sentinel in Python.
undefined = object()
The undefined object above is unique and doesn't do much of anyt...
What's the difference between “groups” and “captures” in .NET regular expressions?
...avior causes group's specification, like (...)(...), (...){2} or (.{3}){2} etc.
Hopefully it will help shed some light on the differences between Captures, Groups and Matches as well.
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imp...
Haskell Type vs Data Constructor
...ide what arguments they are going to put in.
A case study
As the home stretch here, we can consider the Maybe a type. Its definition is
data Maybe a = Nothing
| Just a
Here, Maybe is a type constructor that returns a concrete type. Just is a data constructor that returns a value. N...
What does “dereferencing” a pointer mean?
...igher level libraries and applications, but code for OSes, device drivers, etc. may need to rely on behaviour left undefined by the C or C++ Standard, that is nevertheless well defined by their specific implementation or hardware.
...
What are the effects of exceptions on performance in Java?
... the exceptions themselves, the exact actions taken in exception handlers, etc.
The upshot is that when an exception isn't thrown, you don't pay a cost, so when the exceptional condition is sufficiently rare exception handling is faster than using an if every time. The full post is very much worth...
How to strip HTML tags from a string in SQL Server?
...tween the tags. Ideally also replacing things like &lt; with < , etc.
11 Answers
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How do I list all files of a directory?
...name:
import os
# Getting the current work directory (cwd)
thisdir = os.getcwd()
# r=root, d=directories, f = files
for r, d, f in os.walk(thisdir):
for file in f:
if file.endswith(".docx"):
print(os.path.join(r, file))
os.listdir(): get files in the current directory...
What does the Java assert keyword do, and when should it be used?
... try to trap, log, or retry/recover from OutOfMemoryError, AssertionError, etc.
– Aleksandr Dubinsky
Jun 16 '16 at 21:39
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Is it possible to cache POST methods in HTTP?
...the cached entity (per section 13.10), so that e.g. a subsequent GET must fetch a fersh copy and b) that the POST's response can be cached (per section 9.5), so that e.g. a subsequent POST can receive the same response?
– Diomidis Spinellis
Aug 14 '11 at 21:12
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