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What do (lambda) function closures capture?
...the name and scope of the variable, not the object it's pointing to. Since all the functions in your example are created in the same scope and use the same variable name, they always refer to the same variable.
EDIT: Regarding your other question of how to overcome this, there are two ways that com...
Creating a blocking Queue in .NET?
...threads reading from the same queue. If the queue reaches a specific size all threads that are filling the queue will be blocked on add until an item is removed from the queue.
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static constructors in C++? I need to initialize private static objects
... to have a class with a private static data member (a vector that contains all the characters a-z). In java or C#, I can just make a "static constructor" that will run before I make any instances of the class, and sets up the static data members of the class. It only gets run once (as the variables ...
Why would $_FILES be empty when uploading files to PHP?
I have WampServer 2 installed on my Windows 7 computer. I'm using Apache 2.2.11 and PHP 5.2.11. When I attempt to upload any file from a form, it seems to upload, but in PHP, the $_FILES array is empty. There is no file in the c:\wamp\tmp folder. I have configured php.ini to allow file uploads...
What is the copy-and-swap idiom?
...s arguably the most nuanced and difficult. How should it be done? What pitfalls need to be avoided?
The copy-and-swap idiom is the solution, and elegantly assists the assignment operator in achieving two things: avoiding code duplication, and providing a strong exception guarantee.
How does it wor...
Print current call stack from a method in Python code
In Python, how can I print the current call stack from within a method (for debugging purposes).
7 Answers
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Can I install Python windows packages into virtualenvs?
Virtualenv is great: it lets me keep a number of distinct Python installations so that different projects' dependencies aren't all thrown together into a common pile.
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How to set child process' environment variable in Makefile
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I have GNU make 3.81, and all: <\n\t>export PROJ_ROOT=$(CURDIR)<\n\t>echo $(PROJ_ROOT)<\n> outputs the correct expansion for the first row, but only echo for the second one. PROJ_ROOT is not set after running make. Spaces around = gi...
Duplicate symbols for architecture x86_64 under Xcode
...at defines an Objective-C class or category. While this option will
typically result in a larger executable (due to additional object code
loaded into the application), it will allow the successful creation of
effective Objective-C static libraries that contain categories on
existing classes...
How to run code when a class is subclassed? [duplicate]
...- Watcher subclasses type, not object. 2 - SuperClass has no superclass at all, not object. I'm just so used to writing down object as a superclass for every class I defined that I somehow missed it that this code was using something else. Although there doesn't seem to be any harm in making SuperCl...