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performSelector may cause a leak because its selector is unknown
...s for a reason. It's very rare that this warning should simply be ignored, and it's easy to work around. Here's how:
if (!_controller) { return; }
SEL selector = NSSelectorFromString(@"someMethod");
IMP imp = [_controller methodForSelector:selector];
void (*func)(id, SEL) = (void *)imp;
func(_contr...
Chaining multiple filter() in Django, is this a bug?
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The way I understand it is that they are subtly different by design (and I am certainly open for correction): filter(A, B) will first filter according to A and then subfilter according to B, while filter(A).filter(B) will return a row that ma...
Git pull without checkout?
I'm used to running git pull and other commands from within a branch I'm working on. But I have set up a development server that several people work on, so I don't want to have to switch branches when I do it. If I want to update an existing branch on the dev server from the github repository we a...
Why should I use 'li' instead of 'div'?
...or semantic correctness. HTML has the ability to express lists of things, and it helps the Google robot, screen readers, and all manner of users who don't care solely about the presentation of the site understand your content better.
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How do I remove the file suffix and path portion from a path string in Bash?
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Here's how to do it with the # and % operators in Bash.
$ x="/foo/fizzbuzz.bar"
$ y=${x%.bar}
$ echo ${y##*/}
fizzbuzz
${x%.bar} could also be ${x%.*} to remove everything after a dot or ${x%%.*} to remove everything after the first dot.
Example:
$ x=...
Is there a .NET equivalent to Apache Hadoop? [closed]
So, I've been looking at Hadoop with keen interest, and to be honest I'm fascinated, things don't get much cooler.
15 Ans...
Saving an Object (Data persistence)
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You could use the pickle module in the standard library.
Here's an elementary application of it to your example:
import pickle
class Company(object):
def __init__(self, name, value):
self.name = name
self.value = value
with open('company_data....
Function Pointers in Java
This may be something common and trivial, but I seem to be having trouble finding a concrete answer. In C# there is a concept of delegates, which relates strongly to the idea of function pointers from C++. Is there a similar functionality in Java? Given that pointers are somewhat absent, what is the...
How do I iterate over a range of numbers defined by variables in Bash?
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seq involves the execution of an external command which usually slows things down. This may not matter but it becomes important if you're writing a script to handle lots of data.
– paxdiablo
Oct 4 '08 at 1:45
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Difference in make_shared and normal shared_ptr in C++
Many google and stackoverflow posts are there on this, but I am not able to understand why make_shared is more efficient than directly using shared_ptr .
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