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How can i tell if an object has a key value observer attached
...removeObservers: for a key path and that key path has not been registered, it cracks the sads. like -
10 Answers
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Which is the best Linux C/C++ debugger (or front-end to gdb) to help teaching programming? [closed]
I teach a sort of "lite" C++ programming course to novices ("lite" meaning no pointers, no classes, just plain old C, plus references and STL string and vectors). Students have no previous experience in programming, so I believe that using an interactive debugger would help them understand program f...
Why is using the JavaScript eval function a bad idea?
...hallenging
(no line numbers, etc.)
eval'd code executes slower (no opportunity to compile/cache eval'd code)
Edit: As @Jeff Walden points out in comments, #3 is less true today than it was in 2008. However, while some caching of compiled scripts may happen this will only be limited to scripts that...
Make anchor link go some pixels above where it's linked to
...o do the work of jumping to the anchor for us and then we will use that position to offset from.
EDIT 1:
As was pointed out by @erb, this only works if you are on the page while the hash is changed. Entering the page with a #something already in the URL does not work with the above code. Here is a...
std::vector versus std::array in C++
...ap, that grows and shrinks automatically if elements are added or removed. It provides all the hooks (begin(), end(), iterators, etc) that make it work fine with the rest of the STL. It also has several useful methods that let you perform operations that on a normal array would be cumbersome, like e...
How do I force a DIV block to extend to the bottom of a page even if it has no content?
...o get the content div to stretch all the way to the bottom of the page but it's only stretching if there's content to display. The reason I want to do this is so the vertical border still appears down the page even if there isn't any content to display.
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Where do I find the definition of size_t?
I see variables defined with this type but I don't know where it comes from, nor what is its purpose. Why not use int or unsigned int? (What about other "similar" types? Void_t, etc).
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How to throw an exception in C?
... In C the errors are notified by the returned value of the function, the exit value of the process, signals to the process (Program Error Signals (GNU libc)) or the CPU hardware interruption (or other notification error form the CPU if there is)(How processor handles the case of division by zero).
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Confused about stdin, stdout and stderr?
I am rather confused with the purpose of these three files. If my understanding is correct, stdin is the file in which a program writes into its requests to run a task in the process, stdout is the file into which the kernel writes its output and the process requesting it accesses the informatio...
What are the disadvantages of using persistent connection in PDO
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Please be sure to read this answer below, which details ways to mitigate the problems outlined here.
The same drawbacks exist using PDO as with any other PHP database interface that does persistent connections: if your script terminates unexpectedly in the middle of database operations...