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Why do we need virtual functions in C++?
...eneric food, cats eat rats, all without virtual.
Let's change it a little now so that eat() is called via an intermediate function (a trivial function just for this example):
// This can go at the top of the main.cpp file
void func(Animal *xyz) { xyz->eat(); }
Now our main function is:
Anima...
performSelector may cause a leak because its selector is unknown
...e (the (void *) on the right hand side simply tells the compiler that you know what you're doing and not to generate a warning since the pointer types don't match).
Finally, you call the function pointer2.
Complex Example
When the selector takes arguments or returns a value, you'll have to change...
How do I use spaces in the Command Prompt?
...whole command had to be enclosed again by another pair of quotation marks. Now it works! Thanks!
– Arise
May 30 '13 at 6:36
...
Preferred way to create a Scala list
...odify it, use a tail recursive method, and probably others that I don't know about.
10 Answers
...
Iterating through a JSON object
...nt:
from __future__ import print_function
for song in json_object:
# now song is a dictionary
for attribute, value in song.items():
print(attribute, value) # example usage
NB: You could use song.iteritems instead of song.items if in Python 2.
...
Re-raise exception with a different type and message, preserving existing information
...ture, the __cause__ attribute is set. The built-in exception handler also knows how to report the exception's “cause” and “context” along with the traceback.
In Python 2, it appears this use case has no good answer (as described by Ian Bicking and Ned Batchelder). Bummer.
...
Parse a .py file, read the AST, modify it, then write back the modified source code
...asy, without writing new .py files! If you expand your question to let us know what you actually want to accomplish, new .py files will probably not be involved in the answer at all; I have seen hundreds of Python projects doing hundreds of real-world things, and not a single one of them needed to e...
How do I print the elements of a C++ vector in GDB?
...db wiki page particularly readable, maybe because it's "slightly" outdated now? For instance, I had the impression that the suggested content of the $HOME/.gdbinit was necessary. At the moment I end up with no such file at all and gdb correctly showing the content of std::vector. However, since duri...
Chrome Extension how to send data from content script to popup.html
I know this this has been asked in numerous posts but honestly I don't get them. I am new to JavaScript, Chrome Extensions and everything and I have this class assignment.
So I need to make a plugin that would count DOM objects on any given page using Cross Domain Requests.
I've been able to achiev...
Does Swift support reflection?
...intln("Type: \(type)") //Unfortunately this prints only "Type: Metatype"
Now assuming TestObject extends NSObject
var clazz: NSObject.Type = TestObject.self
var instance : NSObject = clazz()
if let testObject = instance as? TestObject {
println("yes!") //prints "yes!"
}
Currently, there is...