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How do I find where an exception was thrown in C++?
... seems illogical for a program compiled to contain debug symbols not to notify me of where in my code an exception was generated.
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Python: How do I make a subclass from a superclass?
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The only reason to avoid super is if you don't understand the differences between how super works in Python, and how super/parent works in other languages. Admittedly this is not obvious to people coming from other languages, but I wouldn't conclude that that...
Recursive lambda functions in C++11
...ever it's initialized with, but what you're initializing it with needs to know what its type is (in this case, the lambda closure needs to know the types it's capturing). Something of a chicken-and-egg problem.
On the other hand, a fully specified function object's type doesn't need to "know" anyt...
How to add a 'or' condition in #ifdef
How can I add a 'or' condition in #ifdef ?
3 Answers
3
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What does 'require: false' in Gemfile mean?
...probably it does more requires of its own. Even if you require 'yaml', you now have the YAML module as an object in memory.
– Nathan Long
Oct 17 '13 at 19:31
2
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How to override the [] operator in Python?
... key):
return key * 2
myobj = MyClass()
myobj[3] #Output: 6
And if you're going to be setting values you'll need to implement the __setitem__ method too, otherwise this will happen:
>>> myobj[5] = 1
Traceback (most recent call last):
File "<stdin>", line 1, in <module...
What's the difference between eval, exec, and compile?
...built-in function (both are built-in functions in Python 3).
It is a well-known fact that the official syntax of exec in Python 2 is exec code [in globals[, locals]].
Unlike majority of the Python 2-to-3 porting guides seem to suggest, the exec statement in CPython 2 can be also used with syntax th...
Object of custom type as dictionary key
... hash(self.name) looks nicer than self.name.__hash__(), and if you do and you can do hash((x, y)) to avoid XORing yourself.
– Rosh Oxymoron
Feb 4 '11 at 19:02
5
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Accessing Object Memory Address
...ch is guaranteed to be unique and
constant for this object during its
lifetime. Two objects with
non-overlapping lifetimes may have the
same id() value. (Implementation note:
this is the address of the object.)
So in CPython, this will be the address of the object. No such guarantee for ...
correct way to use super (argument passing)
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If you're going to have a lot of inheritence (that's the case here) I suggest you to pass all parameters using **kwargs, and then pop them right after you use them (unless you need them in upper classes).
class First(object)...