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Selectors in Objective-C?
First, I'm not sure I really understand what a selector is. From my understanding, it's the name of a method, and you can assign it to a class of type 'SEL' and then run methods such as respondToSelector to see if the receiver implements that method. Can someone offer up a better explanation?
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Catch an exception thrown by an async void method
Using the async CTP from Microsoft for .NET,
is it possible to catch an exception thrown by an async method in the calling method?
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How can I reverse the order of lines in a file?
I'd like to reverse the order of lines in a text file (or stdin), preserving the contents of each line.
25 Answers
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Using ConfigurationManager to load config from an arbitrary location
I'm developing a data access component that will be used in a website that contains a mix of classic ASP and ASP.NET pages, and need a good way to manage its configuration settings.
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Apply a function to every row of a matrix or a data frame
Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R?
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EF Migrations: Rollback last applied migration?
This looks like a really common task, but I can't find an easy way to do it.
14 Answers
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How to remove all null elements from a ArrayList or String Array?
I try with a loop like that
18 Answers
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Java Security: Illegal key size or default parameters?
I had asked a question about this earlier, but it didn't get answered right and led nowhere.
19 Answers
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Null check in an enhanced for loop
What is the best way to guard against null in a for loop in Java?
11 Answers
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Is it expensive to use try-catch blocks even if an exception is never thrown?
We know that it is expensive to catch exceptions. But, is it also expensive to use a try-catch block in Java even if an exception is never thrown?
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