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Test for existence of nested JavaScript object key
...don't want a TypeError because if one of the members is null or undefined, and you try to access a member, an exception will be thrown.
You can either simply catch the exception, or make a function to test the existence of multiple levels, something like this:
function checkNested(obj /*, level1, ...
How to create a DataTable in C# and how to add rows?
... DataView with filter other than CurrentRows.
– Salamander2007
Jun 25 '09 at 7:44
@phoenix: I just wanted the question...
Converting between datetime, Timestamp and datetime64
...d by np.datetime64 as time in UTC.
To convert datetime to np.datetime64 and back (numpy-1.6):
>>> np.datetime64(datetime.utcnow()).astype(datetime)
datetime.datetime(2012, 12, 4, 13, 34, 52, 827542)
It works both on a single np.datetime64 object and a numpy array of np.datetime64.
Th...
A proper wrapper for console.log with correct line number?
I'm now developing an application, and place a global isDebug switch. I would like to wrap console.log for more convenient usage.
...
SqlAlchemy - Filtering by Relationship Attribute
I don't have much experience with SQLAlchemy and I have a problem, which I can't solve. I tried searching and I tried a lot of code.
This is my Class (reduced to the most significant code):
...
What is the volatile keyword useful for?
...trol whether some code continues a loop. The loop tests the volatile value and continues if it is true. The condition can be set to false by calling a "stop" method. The loop sees false and terminates when it tests the value after the stop method completes execution.
The book "Java Concurrency in P...
How to write the Fibonacci Sequence?
...
There is lots of information about the Fibonacci Sequence on wikipedia and on wolfram. A lot more than you may need. Anyway it is a good thing to learn how to use these resources to find (quickly if possible) what you need.
Write Fib sequence formula to infinite
In math, it's given in a recurs...
How do I call setattr() on the current module?
... scope it's called at: the module's variables when called at global scope, and then it's OK to use it R/W, but the function's variables when called in a function, and then it must be treated as R/O -- the Python online docs can be a bit confusing about this specific distinction).
...
Passing a std::array of unknown size to a function
... answered Jun 17 '13 at 20:30
Andy ProwlAndy Prowl
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Is there a way to instantiate objects from a string holding their class name?
...<DerivedA>;
map["DerivedB"] = &createInstance<DerivedB>;
And then you can do
return map[some_string]();
Getting a new instance. Another idea is to have the types register themself:
// in base.hpp:
template<typename T> Base * createT() { return new T; }
struct BaseFactor...