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Why doesn't list have safe “get” method like dictionary?
...name, not directly access the 37th item in the dictionary (which would be more like what you're asking of your list).
Of course, you can easily implement this yourself:
def safe_list_get (l, idx, default):
try:
return l[idx]
except IndexError:
return default
You could even monkeypatc...
Difference between pre-increment and post-increment in a loop?
Is there a difference in ++i and i++ in a for loop? Is it simply a syntax thing?
22 Answers
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Why can I throw null in Java? [duplicate]
...ttempting to throw null itself throws a NullPointerException.
In other words, throw checks that its argument is nonnull, and if it is null, it throws a NullPointerException.
JLS 14.18 specifies this behavior:
If evaluation of the Expression completes normally, producing a null value, then an...
Clone only one branch [duplicate]
... how I could clone only one branch instead of cloning the whole Git repository.
4 Answers
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Union of dict objects in Python [duplicate]
...
This question provides an idiom. You use one of the dicts as keyword arguments to the dict() constructor:
dict(y, **x)
Duplicates are resolved in favor of the value in x; for example
dict({'a' : 'y[a]'}, **{'a', 'x[a]'}) == {'a' : 'x[a]'}
...
How do I update all my CPAN modules to their latest versions?
...tdated
BTW: If you are using perlbrew then you will need to repeat this for every Perl you have installed under it.
You can find out more about cpanminus and cpan-outdated at the Github repos here:
https://github.com/miyagawa/cpanminus
https://github.com/tokuhirom/cpan-outdated
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wait() or sleep() function in jquery?
... a delay of some period of time (measured in milliseconds). However, an important note: because of the nature of javascript, the rest of the code continues to run after the timer is setup:
$('#someid').addClass("load");
setTimeout(function(){
$('#someid').addClass("done");
}, 2000);
// Any code...
Nginx reverse proxy causing 504 Gateway Timeout
...ass to get the actual web application from the upstream server running on port 8001.
8 Answers
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How can I ssh directly to a particular directory?
...ten have to login to one of several servers and go to one of several directories on those machines. Currently I do something of this sort:
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bash: pip: command not found
I downloaded pip and ran python setup.py install and everything worked just fine. The very next step in the tutorial is to run pip install <lib you want> but before it even tries to find anything online I get an error "bash: pip: command not found".
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