Failing to create a std::ranges::iota_view with value and bound

user_2226708 0
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I tried to create a std::ranges::iota_view with a value and a bound:

#include <ranges>
#include <vector>

int main() {
  std::vector v{1,2,3};
  auto indices = std::ranges::views::iota(0, v.size());
}

link to program on godbolt

But clang 11.0.0 fails to compile with the error message:

no viable constructor or deduction guide for deduction of template arguments of 'iota_view'

What am I doing wrong?

range c++
1 Answers

From https://en.cppreference.com/w/cpp/ranges/iota_view

Note that the [deduction] guide protects itself against signed/unsigned mismatch bugs, like views::iota(0, v.size()), where 0 is a (signed) int and v.size() is an (unsigned) std::size_t.

This will work:

auto indices = std::ranges::views::iota(0u, v.size());
                                         ^ unsigned zero literal

Unfortunately Clang seems to have another bug, but it works in gcc; or you can use range-v3.

user_5672920
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