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Is System.nanoTime() completely useless?
...ventov's answer offers a more up-to-date perspective.
That post is wrong, and nanoTime is safe. There's a comment on the post which links to a blog post by David Holmes, a realtime and concurrency guy at Sun. It says:
System.nanoTime() is implemented using the QueryPerformanceCounter/QueryPerfo...
When and why would you seal a class?
In C# and C++/CLI the keyword sealed (or NotInheritable in VB) is used to protect a class from any inheritance chance (the class will be non-inheritable). I know that one feature of object-oriented programming is inheritance and I feel that the use of sealed goes against this feature, it stop...
What does asterisk * mean in Python? [duplicate]
...nary.
Also, see Function Calls.
Assuming that one knows what positional and keyword arguments are, here are some examples:
Example 1:
# Excess keyword argument (python 2) example:
def foo(a, b, c, **args):
print "a = %s" % (a,)
print "b = %s" % (b,)
print "c = %s" % (c,)
print a...
Capturing mobile phone traffic on Wireshark
...
Here are some suggestions:
For Android phones, any network: Root your phone, then install tcpdump on it. This app is a tcpdump wrapper that will install tcpdump and enable you to start captures using a GUI. Tip: You will need to make sure you supply the ri...
How do you know when to use fold-left and when to use fold-right?
I'm aware that fold-left produces left-leaning trees and fold-right produces right-leaning trees, but when I reach for a fold, I sometimes find myself getting bogged down in headache-inducing thought trying to determine which kind of fold is appropriate. I usually end up unwinding the entire proble...
Why do we need Abstract factory design pattern?
...tract Factory has been accepted as the solution.
To the best of my understanding, these questions represent real concerns or problems that people had, so that should get you started with some real-life examples:
Is there a pattern for initializing objects created via a DI container
Can't combine ...
Difference between DOM parentNode and parentElement
... possible terms, what is the difference between classical DOM parentNode and newly introduced in Firefox 9 parentElement
...
How do I convert seconds to hours, minutes and seconds?
...his is the best way, IMHO, as you can then use arithmetic on the timedelta and any datetime objects.
– Matthew Schinckel
Apr 22 '09 at 3:13
13
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How to merge dictionaries of dictionaries?
...for key in b:
if key in a:
if isinstance(a[key], dict) and isinstance(b[key], dict):
merge(a[key], b[key], path + [str(key)])
elif a[key] == b[key]:
pass # same leaf value
else:
raise Exception('Conflict at %...
How to make a DIV visible and invisible with JavaScript
...roperty of that element. To show/hide, you can use two properties: display and visibility, which have slightly different effects:
Adjusting style.display will look as if element is not present at all ("removed").
elem.style.display = 'none'; // hide
elem.style.display = 'block'; // show - use this...