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if A vs if A is not None:
...
The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...
What is the fastest substring search algorithm?
...s-Pratt uses a partial match table.
Rabin-Karp uses running hashes.
They all trade overhead for reduced comparisons to a different degree, so the real world performance will depend on the average lengths of both the needle and haystack. The more initial overhead, the better with longer inputs. W...
What are the mechanics of short string optimization in libc++?
...ver, I would like to know in more detail how it works in practice, specifically in the libc++ implementation:
2 Answers
...
Is this object-lifetime-extending-closure a C# compiler bug?
...L_000e: ldloc.0
IL_000f: ldc.r8 42
IL_0018: ldc.r8 1
IL_0021: call float64 [mscorlib]System.Math::Pow(float64, float64)
IL_0026: stfld float64 ConsoleApplication1.Program/Foo/'<>c__DisplayClass1'::capturedVariable
IL_002b: ldarg.0
IL_002c: ldloc.0
IL_002d: ldftn ins...
Remove all occurrences of a value from a list?
...on over the filter+lambda; the former is more readable in addition to generally more efficient.
– habnabit
Jul 21 '09 at 4:28
17
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How to use filter, map, and reduce in Python 3
... longer return lists:
[...]
map() and filter() return iterators. If you really need a list, a quick fix is e.g. list(map(...)), but a better fix is often to use a list comprehension (especially when the original code uses lambda), or rewriting the code so it doesn’t need a list at all. Particular...
What is the difference between onBlur and onChange attribute in HTML?
... answered Feb 19 '14 at 10:43
php-b-graderphp-b-grader
2,7431010 gold badges3535 silver badges4949 bronze badges
...
Return positions of a regex match() in Javascript?
... @OnurYıldırım - here's a jsfiddle of it working...I've tested it all the way back to IE5...works great: jsfiddle.net/6uwn1vof
– Jimbo Jonny
Mar 29 '16 at 22:34
1
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Styling an input type=“file” button
... is explained here. Just putting that link here, since this answer is basically a link-only answer anyway.
– Joeytje50
May 7 '14 at 16:30
10
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Difference between except: and except Exception as e: in Python
... print e.message, e.args
...
>>> catch()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<stdin>", line 3, in catch
BaseException
Which a bare except does:
>>> def catch():
... try:
... raise BaseException()
... ...