Function block_

gil/std.base.hpp:76–76

static constexpr auto break_ = lib::code::ctrl::Break{};

static constexpr auto block_(auto... code) { return loop_(code..., break_); }

static constexpr auto while_(auto cond) noexcept {
  return [=](auto... code) { return loop_(if_(cond)(code...)->else_(break_)); };