Storing expression template functors

Posted by UncaughtException on Stack Overflow See other posts from Stack Overflow or by UncaughtException
Published on 2010-03-19T10:22:14Z Indexed on 2010/03/19 10:31 UTC
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Hello guys,

at the moment I'm really interested in expression templates and want to code a library for writing and differentiating mathematical functions with a lambda-style syntax. At the moment, I'm able to write (_x * _x)(2); and get the correct result 4. But I would really like to do something like MathFunction f = _x * _x; f(2);, but I don't have any ideas on how to cope with the recursive expression templates on the right side. Is it possible to achieve this without using the 'auto'-Keyword instead of MathFunction or having to make the operator() virtual?

Thanks for your help!

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