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UnboundLocalError on local variable when reassigned after first use
...t since it WON'T have the luxury of a second pass, the lexer does a little extra work to make life easier later on. Only, then it sees the OPERATOR, sees that the rules say "if you have an operator += the left hand side must have been initialized" and says "whoops!"
The point here is that it hasn...
What's the pythonic way to use getters and setters?
... eg java. Instead of making everything private by default and writing some extra code when it is needed publicly in python you can make everything public and add privacy later on
– idclev 463035818
Aug 29 '18 at 10:27
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What is the difference between old style and new style classes in Python?
...I can see of the new-style classes. There is a disadvantage, which is the extra typing of (object).
– recursive
May 3 '11 at 12:45
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Why NSUserDefaults failed to save NSMutableDictionary in iOS?
...y object in NSUserDefaults . The key type in NSMutableDictionary is NSString , the value type is NSArray , which contains a list of object which implements NSCoding . Per document, NSString and NSArray both are conform to NSCoding .
...
Populating a razor dropdownlist from a List in MVC
... {
Value = x.UserRoleId.ToString(),
Text = x.UserRole
});
return new SelectList(roles, "Value", "Text");
}
public ActionResult AddNewUser()
{
var model = new UserRoleViewModel
...
Index (zero based) must be greater than or equal to zero
...
Your second String.Format uses {2} as a placeholder but you're only passing in one argument, so you should use {0} instead.
Change this:
String.Format("{2}", reader.GetString(0));
To this:
String.Format("{0}", reader.GetString(2));
...
What's the recommended approach to resetting migration history using Django South?
...t a longer variant of manage.py convert_to_south my_app, but I prefer that extra control, in such delicate situation as modifying the production database.
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Why do C and C++ compilers allow array lengths in function signatures when they're never enforced?
... return bar;
}
You have to access the elements like this: foo.a[1]. The extra ".a" might look weird, but this trick adds great functionality to the C language.
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Initialize parent's protected members with initialization list (C++)
...t along. Something like:
class Parent
{
protected:
Parent( const std::string& something ) : something( something )
{}
std::string something;
}
class Child : public Parent
{
private:
Child() : Parent("Hello, World!")
{
}
}
...
Is “IF” expensive?
...t it doesn't need once the outcome of the branch is known. This saves the extra memory access of a typical architecture in the event that it branches along the unpredicted path.
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