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Check if class already assigned before adding
...
Just call addClass(). jQuery will do the check for you. If you check on your own, you are doubling the work, since jQuery will still run the check for you.
...
Is there a difference between “raise exception()” and “raise exception” without parenthesis?
...said, even though the semantics are the same, the first form is microscopically faster, and the second form is more flexible (because you can pass it arguments if needed).
The usual style that most people use in Python (i.e. in the standard library, in popular applications, and in many books) is t...
Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
...of the work can
be avoided. With a slightly smarter
linker than is typically used, it is
possible to remove some of these
inefficiencies. This is discussed in
§6.2.3 and §6.2.5.
Since the report was written in 2006 one would hope that many of the recommendations would have been incorpo...
Some questions about Automatic Reference Counting in iOS5 SDK
...nk will be completed) for iOS 4.3.
I just read about ARC in iOS 5, and basically I understood that we will never need to release and retain objects anymore. My questions are:
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promise already under evaluation: recursive default argument reference or earlier problems?
...easier (for me) way to avoid the problem: just specify the argument in the call instead of the definition.
This does not work:
x = 4
my.function <- function(x = x){}
my.function() # recursive error!
but this does work:
x = 4
my.function <- function(x){}
my.function(x = x) # works fine!
Fu...
Does every Javascript function have to return a value?
...returned nothing at all, there would be no way of knowing what and when to call the next function, or to call event handlers and the like.
So to recap: No, a JS function needn't return anything as far as your code goes. But as far as the JS engines are concerned: a function always returns something...
How to safely open/close files in python 2.4
...
See docs.python.org:
When you’re done with a file, call f.close() to close it and free up any system resources taken up by the open file. After calling f.close(), attempts to use the file object will automatically fail.
Hence use close() elegantly with try/finally:
f = ope...
node.js global variables?
... title: 'node',
assert: [Function],
version: 'v0.6.5',
_tickCallback: [Function],
moduleLoadList:
[ 'Binding evals',
'Binding natives',
'NativeModule events',
'NativeModule buffer',
'Binding buffer',
'NativeModule assert',
'N...
Why is Class.newInstance() “evil”?
...ll the other reflection-based invocation methods throw a checked exception called InvocationTargetException that wraps any throwable thrown by the invoked method. Class.newInstance won't do that---it will throw the checked exception directly. The downside is that javac won't let you try to catch tho...
Why does google.load cause my page to go blank?
...se_thread/thread/e07c2606498094e6
Using one of the ideas, you could use a callback for the load to force it use append rather than doc.write:
setTimeout(function(){google.load('visualization', '1', {'callback':'alert("2 sec wait")', 'packages':['corechart']})}, 2000);
This demonstrates the 2 sec...