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Capturing Groups From a Grep RegEx
... use grep multiple times within a pipeline to first reduce your line to a known format, and then to extract just the bit you want. (Although tools like cut and sed are far better at this).
Suppose for the sake of argument that your pattern was a bit simpler: [0-9]+_([a-z]+)_ You could extract this ...
How do you express binary literals in Python?
... 0b_1110_0101
Changed in version 3.6: Underscores are now allowed for grouping purposes in literals.
Other ways of expressing binary:
You can have the zeros and ones in a string object which can be manipulated (although you should probably just do bitwise operations on the in...
Python function overloading
I know that Python does not support method overloading, but I've run into a problem that I can't seem to solve in a nice Pythonic way.
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Why does !{}[true] evaluate to true in JavaScript?
... @Cruncher If a is undefined, and b is undefined, how can we possibly know that a != b? Particularly when the only known characteristic of the two variables is exactly the same.
– LJ2
Oct 31 '13 at 18:15
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What's the best way to parse command line arguments? [closed]
...hon 2.3 thru 2.6. For python 2.7+ it is not the best answer as argparse is now part of the standard library and optparse deprecrated.
– matt wilkie
Feb 28 '11 at 19:47
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Unresolved Import Issues with PyDev and Eclipse
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I tried this and now I can't start my DEV server. How do I replace the file?
– Lee Loftiss
May 2 '19 at 13:49
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Can I use a binary literal in C or C++?
...'ve seen a number of embedded-systems compilers that support it. I don't know any particular reason it shouldn't be a standard language feature.
– supercat
Aug 1 '11 at 21:34
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What is stdClass in PHP?
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I hope you know that object isn't the derived class of "all" objects in Python... At least, not until you are forced to derive from object in Python 3.0
– monokrome
Sep 21 '10 at 23:35
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How to sort two lists (which reference each other) in the exact same way
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Now they're converted to Numpy arrays twice ;)
– BenB
Jul 8 '15 at 19:32
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String concatenation vs. string substitution in Python
... large boosts in performance..."
If performance matters, this is good to know.
However, performance problems I've seen have never come down to string operations. I've generally gotten in trouble with I/O, sorting and O(n2) operations being the bottlenecks.
Until string operations are the perfor...