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How to know if an object has an attribute in Python
...n is that, if the property is likely to be there most of the time, simply call it and either let the exception propagate, or trap it with a try/except block. This will likely be faster than hasattr. If the property is likely to not be there most of the time, or you're not sure, using hasattr will pr...
What's the dSYM and how to use it? (iOS SDK)
...es. I guess this is a debugging related file, but I don't know what it is, and how to use it.
2 Answers
...
How to toggle a value in Python
What is the most efficient way to toggle between 0 and 1 ?
17 Answers
17
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Python JSON serialize a Decimal object
I have a Decimal('3.9') as part of an object, and wish to encode this to a JSON string which should look like {'x': 3.9} . I don't care about precision on the client side, so a float is fine.
...
Android - Package Name convention
...ou consider each period ('.') in the application name as a path separator, all applications from a publisher would sit together in the path hierarchy.
So, for instance, packages from Adobe would be of the form:
com.adobe.reader (Adobe Reader)
com.adobe.photoshop (Adobe Photoshop)
com.adobe.ideas ...
How do I trim leading/trailing whitespace in a standard way?
... C? I'd roll my own, but I would think this is a common problem with an equally common solution.
38 Answers
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Cost of len() function
...
Calling len() on those data types is O(1) in CPython, the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComple...
Changing the cursor in WPF sometimes works, sometimes doesn't
...deCursor:
Mouse.OverrideCursor = Cursors.Wait;
try
{
// do stuff
}
finally
{
Mouse.OverrideCursor = null;
}
This overrides the cursor for your application rather than just for a part of its UI, so the problem you're describing goes away.
...
Nested Models in Backbone.js, how to approach
...n modify the parse method to change a attributes around in the object, but all of that is actually pretty unmaintainable code IMO, and feels more of a hack than a solution.
Here's what I suggest for your example:
First define your Layout Model like so.
var layoutModel = Backbone.Model.extend({});...
Why should I prefer to use member initialization lists?
...tyle. For class members which are classes, then it avoids an unnecessary call to a default constructor. Consider:
class A
{
public:
A() { x = 0; }
A(int x_) { x = x_; }
int x;
};
class B
{
public:
B()
{
a.x = 3;
}
private:
A a;
};
In this case, the construct...