in include/range/v3/algorithm/equal.hpp [38:48]
bool nocheck(I0 begin0, S0 end0, I1 begin1, S1 end1, C pred_,
P0 proj0_, P1 proj1_) const
{
auto &&pred = as_function(pred_);
auto &&proj0 = as_function(proj0_);
auto &&proj1 = as_function(proj1_);
for(; begin0 != end0 && begin1 != end1; ++begin0, ++begin1)
if(!pred(proj0(*begin0), proj1(*begin1)))
return false;
return begin0 == end0 && begin1 == end1;
}