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Best way to iterate through a Perl array
...ay elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)
#5 might be similar.
In terms memory usage: They're all the same except for #5.
for (@a) is special-cased to avoid flattening the array. The loop iterates over the indexes of the array...
Fastest exit strategy for a Panic Button in Crisis/Abuse Websites? [closed]
...
(ALMOST) FINAL EDIT
OK, I've read all the comments and this is what I think is the best solution but I've also thought of an ALL-LOCAL ALTERNATIVE. I'm open to further improvement/discussion
var panic= function(){
document.body.innerHTML = '';
//th...
How to efficiently count the number of keys/properties of an object in JavaScript?
...t only iterates through the object but also creates a whole new array with all its keys, so it completely fails at answering the question.
– GetFree
Jun 22 '12 at 14:28
43
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How to throw an exception in C?
...and caught in the program, but the C code portions will remain ignorant of all of this going on except that exception throwing and catching often rely on functions written in C which reside in the C++ libraries. C is used because you can't risk the function called to do throw needing to throw an exc...
Python: most idiomatic way to convert None to empty string?
...
If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
...
How to use the TextWatcher class in Android?
...ich are overridden for the text watcher. you can mask the text which you really wanted to.
– Dinesh Prajapati
Dec 17 '11 at 8:07
2
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How do I import the Django DoesNotExist exception?
...y of the model itself, in this case Answer.
Your problem is that you are calling the get method - which raises the exception - before it is passed to assertRaises. You need to separate the arguments from the callable, as described in the unittest documentation:
self.assertRaises(Answer.DoesNotExis...
How to read keyboard-input?
... mixing different Pythons here (Python 2.x vs. Python 3.x)...
This is basically correct:
nb = input('Choose a number: ')
The problem is that it is only supported in Python 3. As @sharpner answered, for older versions of Python (2.x), you have to use the function raw_input:
nb = raw_input('Choose...
Why are preprocessor macros evil and what are the alternatives?
I have always asked this but I have never received a really good answer; I think that almost any programmer before even writing the first "Hello World" had encountered a phrase like "macro should never be used", "macro are evil" and so on, my question is: why? With the new C++11 is there a real alte...
Why is there no xrange function in Python3?
...Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collec...