c# - What are new features in linq in c#4.0? -

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i c# developer , use linq much. know new features of linq in c#4.0.i know zip method there.is there new methods that?

there new zip() extension method http://msdn.microsoft.com/en-us/library/dd267698.aspx , new ef 4.0 http://msdn.microsoft.com/en-us/data/aa937723 while isn't directly linq, created tuple class tree http://msdn.microsoft.com/en-us/library/system.tuple.aspx , , expanded action<t1, t2...> , func<t1, t2...> 10 parameters. i'm not sure if covariance , contravariance should listed here (ienumerable<t> covariant, , "he" 1 of basic "objects" of linq)


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