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Comment by timtadh | Hacker News Reader

While we are at it Python:

    >>> sum(x*x for x in xrange(1,11))
    385

You could use a map in Python as well, but really, the generator expression is much cleaner:

    >>> sum(map(lambda x: x*x, xrange(1,11)))
    385

Those compute the same value, but I think the point of the C++ stream version is to compute the value using a lazily evaluated infinite list.

The C++ equivalent of your Python would be something like:

    typedef boost::counting_iterator<int> ci;
    auto sum = std::accumulate(ci(0), ci(10), 0, [](auto x, auto y) { return x + (y*y); });

No special streaming library required.

Deleted comment

Oops, my bad. I didn't read the original closely enough.

A solution in the spirit of the post using itertools:

    >>> from itertools import islice,count
    >>> sum(x*x for x in islice(count(1),10))
    385