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What is the difference between cout, cerr, clog of iostream header in c++? When to use which one?
I tried researching the difference between cout , cerr and clog on the internet but couldn't find a perfect answer. I still am not clear on when to use which. Can anyone explain to me, through simple programs and illustrate a perfect situation on when to use which one?
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C# difference between == and Equals()
...resolve to System.Object.ReferenceEquals.
Equals is just a virtual method and behaves as such, so the overridden version will be used (which, for string type compares the contents).
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What is the purpose of the reader monad?
...ify your program to deal with multiple currencies. You need to be able to convert between currencies on the fly. Your first attempt is to define a top level function
type CurrencyDict = Map CurrencyName Dollars
currencyDict :: CurrencyDict
to get spot prices. You can then call this dictionary i...
How to make a flat list out of list of lists?
...for item in sublist]
As evidence, you can use the timeit module in the standard library:
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' '[item for sublist in l for item in sublist]'
10000 loops, best of 3: 143 usec per loop
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'sum(l...
Creating a left-arrow button (like UINavigationBar's “back” style) on a UIToolbar
... that I derived from http://www.teehanlax.com/blog/?p=447
http://www.chrisandtennille.com/pictures/backbutton.psd
I then just created a custom UIView that I use in the customView property of the toolbar item.
Works well for me.
Edit: As pointed out by PrairieHippo, maralbjo found that using th...
Avoiding instanceof in Java
...ng a chain of "instanceof" operations is considered a "code smell". The standard answer is "use polymorphism". How would I do it in this case?
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How can I check if a method is static using reflection?
...ods of a class, how can I do this?
Or, how to differentiate between static and non-static methods.
3 Answers
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How do you build a Singleton in Dart?
...all when it's really a constructor definition. There's the _internal name. And there's the nifty language design point that Dart lets you start out (dart out?) using an ordinary constructor and then, if needed, change it to a factory method without changing all the callers.
– J...
Variable declaration placement in C
...on of s as a GNU extension, even though it's not part of the C89 or ANSI standard. If you want to adhere strictly to those standards, you must pass the -pedantic flag.
The declaration of c at the start of a { } block is part of the C89 standard; the block doesn't have to be a function.
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How do you perform a CROSS JOIN with LINQ to SQL?
....SelectMany(t1 => sequence2.Select(t2 => Tuple.Create(t1, t2)));
}
And use like:
vals1.CrossJoin(vals2)
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