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C++ Redefinition Header Files (winsock2.h)
How do I prevent from including header files twice? The problem is I'm including the in MyClass.h and then I'm including MyClass.h in many files, so it includes multiple times and redefinition error occurs. How to prevent?
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Cannot create an NSPersistentStoreCoordinator with a nil model
...xactly the same error message as the original post. I was wrestling with this for hours.
It was this line in my AppDelegate.m.
NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"[same with name of xcdatamodeld]" withExtension:@"momd"];
For anyone out there searching this error message and ...
Salting Your Password: Best Practices?
I've always been curious... Which is better when salting a password for hashing: prefix, or postfix? Why? Or does it matter, so long as you salt?
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MySQL and GROUP_CONCAT() maximum length
... rows into a single string.
However, the maximum length of the result of this function is 1024 characters.
7 Answers
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Reading specific lines only
...read a file, but I only want to read specific lines, say line #26 and #30. Is there any built-in feature to achieve this?
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Fat models and skinny controllers sounds like creating God models [closed]
...skinny controllers approach, esp. the Rails camp. As a result the routers is basically just figuring out what method to call on what controller and all the controller method does is call the corresponding method on the model and then bring up the view. So I've two concerns here which I don't unders...
Group query results by month and year in postgresql
... month.
extract(year from date) as yyyy : Postgresql's "extract" function is used to extract the YYYY year from the "date" attribute.
sum("Sales") as "Sales" : The SUM() function adds up all the "Sales" values, and supplies a case-sensitive alias, with the case sensitivity maintained by using doub...
How does #include work in C++? [duplicate]
...t if we add #include <bits/stdc++.h> in a C++ program then there is no need to include any other header files. How does #include <bits/stdc++.h> work and is it ok to use it instead of including individual header files?
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How to remove spaces from a string using JavaScript?
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This?
str = str.replace(/\s/g, '');
Example
var str = '/var/www/site/Brand new document.docx';
document.write( str.replace(/\s/g, '') );
Update: Based on this question, this:
str = str.replace(/\s+/g, '');
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Why is this program erroneously rejected by three C++ compilers?
...et), so it cannot move into further processing stages, hence the error. It is entirely possible that your compiler support a mapping from image to basic source character set, but is not required to.
Since this mapping is implementation-defined, you'll need to look at your implementations documenta...