In file included from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_algobase.h:71,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/string:50,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/locale_classes.h:40,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/ios_base.h:41,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/ios:42,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/ostream:38,
                 from iostream:39:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h: In instantiation of 'bool __gnu_cxx::__ops::_Iter_equals_val<_Value>::operator()(_Iterator) [with _Iterator = __gnu_cxx::__normal_iterator<char*, std::__cxx11::basic_string<char> >; _Value = const std::__cxx11::basic_string<char>]':
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_algobase.h:2123:12:   required from 'typename std::iterator_traits< <template-parameter-1-1> >::difference_type std::__count_if(_InputIterator, _InputIterator, _Predicate) [with _InputIterator = __gnu_cxx::__normal_iterator<char*, __cxx11::basic_string<char> >; _Predicate = __gnu_cxx::__ops::_Iter_equals_val<const __cxx11::basic_string<char> >; typename iterator_traits< <template-parameter-1-1> >::difference_type = long int]'
/nix/store/dm8k43g793kzl9rc4s12hh2fdwxwsb67-gcc/include/c++/12.3.0/bits/stl_algo.h:4034:29:   required from 'typename std::iterator_traits< <template-parameter-1-1> >::difference_type std::count(_IIter, _IIter, const _Tp&) [with _IIter = __gnu_cxx::__normal_iterator<char*, __cxx11::basic_string<char> >; _Tp = __cxx11::basic_string<char>; typename iterator_traits< <template-parameter-1-1> >::difference_type = long int]'
foo.cc:11:18:   required from here
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: error: no match for 'operator==' (operand types are 'char' and 'const std::__cxx11::basic_string<char>')
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
In file included from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/string:47:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:1213:5: note: candidate: 'template<class _IteratorL, class _IteratorR, class _Container> bool __gnu_cxx::operator==(const __normal_iterator<_IteratorL, _Container>&, const __normal_iterator<_IteratorR, _Container>&)'
 1213 |     operator==(const __normal_iterator<_IteratorL, _Container>& __lhs,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:1213:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const __gnu_cxx::__normal_iterator<_IteratorL, _Container>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:1221:5: note: candidate: 'template<class _Iterator, class _Container> bool __gnu_cxx::operator==(const __normal_iterator<_Iterator, _Container>&, const __normal_iterator<_Iterator, _Container>&)'
 1221 |     operator==(const __normal_iterator<_Iterator, _Container>& __lhs,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:1221:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const __gnu_cxx::__normal_iterator<_Iterator, _Container>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
In file included from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/x86_64-unknown-linux-gnu/bits/c++allocator.h:33,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/allocator.h:46,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/string:41:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/new_allocator.h:196:9: note: candidate: 'template<class _Up> bool std::operator==(const __new_allocator<char>&, const __new_allocator<_Tp>&)'
  196 |         operator==(const __new_allocator&, const __new_allocator<_Up>&)
      |         ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/new_allocator.h:196:9: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   'const std::__cxx11::basic_string<char>' is not derived from 'const std::__new_allocator<_Tp>'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
In file included from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/iosfwd:40,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/ios:38:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/postypes.h:192:5: note: candidate: 'template<class _StateT> bool std::operator==(const fpos<_StateT>&, const fpos<_StateT>&)'
  192 |     operator==(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/postypes.h:192:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::fpos<_StateT>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/allocator.h:219:5: note: candidate: 'template<class _T1, class _T2> bool std::operator==(const allocator<_CharT>&, const allocator<_T2>&)'
  219 |     operator==(const allocator<_T1>&, const allocator<_T2>&)
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/allocator.h:219:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::allocator<_CharT>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:444:5: note: candidate: 'template<class _Iterator> bool std::operator==(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  444 |     operator==(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:444:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:489:5: note: candidate: 'template<class _IteratorL, class _IteratorR> bool std::operator==(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  489 |     operator==(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:489:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:1674:5: note: candidate: 'template<class _IteratorL, class _IteratorR> bool std::operator==(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1674 |     operator==(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:1674:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::move_iterator<_IteratorL>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:1744:5: note: candidate: 'template<class _Iterator> bool std::operator==(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1744 |     operator==(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_iterator.h:1744:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::move_iterator<_IteratorL>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
In file included from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_algobase.h:64:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_pair.h:640:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator==(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
  640 |     operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/stl_pair.h:640:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::pair<_T1, _T2>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
In file included from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/string:53:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/basic_string.h:3583:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator==(const __cxx11::basic_string<_CharT, _Traits, _Alloc>&, const __cxx11::basic_string<_CharT, _Traits, _Alloc>&)'
 3583 |     operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/basic_string.h:3583:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/basic_string.h:3592:5: note: candidate: 'template<class _CharT> typename __gnu_cxx::__enable_if<std::__is_char<_Tp>::__value, bool>::__type std::operator==(const __cxx11::basic_string<_CharT>&, const __cxx11::basic_string<_CharT>&)'
 3592 |     operator==(const basic_string<_CharT>& __lhs,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/basic_string.h:3592:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::__cxx11::basic_string<_CharT>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/basic_string.h:3607:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator==(const __cxx11::basic_string<_CharT, _Traits, _Alloc>&, const _CharT*)'
 3607 |     operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/basic_string.h:3607:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/basic_string.h:3648:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator==(const _CharT*, const __cxx11::basic_string<_CharT, _Traits, _Alloc>&)'
 3648 |     operator==(const _CharT* __lhs,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/basic_string.h:3648:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const _CharT*' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
In file included from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/locale_facets.h:48,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/basic_ios.h:37,
                 from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/ios:44:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/streambuf_iterator.h:233:5: note: candidate: 'template<class _CharT, class _Traits> bool std::operator==(const istreambuf_iterator<_CharT, _Traits>&, const istreambuf_iterator<_CharT, _Traits>&)'
  233 |     operator==(const istreambuf_iterator<_CharT, _Traits>& __a,
      |     ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/streambuf_iterator.h:233:5: note:   template argument deduction/substitution failed:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/predefined_ops.h:270:24: note:   mismatched types 'const std::istreambuf_iterator<_CharT, _Traits>' and 'char'
  270 |         { return *__it == _M_value; }
      |                  ~~~~~~^~~~~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/allocator.h:205:7: note: candidate: 'bool std::operator==(const allocator<char>&, const allocator<char>&)'
  205 |       operator==(const allocator&, const allocator&) _GLIBCXX_NOTHROW
      |       ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/allocator.h:205:18: note:   no known conversion for argument 1 from 'char' to 'const std::allocator<char>&'
  205 |       operator==(const allocator&, const allocator&) _GLIBCXX_NOTHROW
      |                  ^~~~~~~~~~~~~~~~
In file included from /nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/bits/ios_base.h:46:
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/system_error:444:3: note: candidate: 'bool std::operator==(const error_code&, const error_code&)'
  444 |   operator==(const error_code& __lhs, const error_code& __rhs) noexcept
      |   ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/system_error:444:32: note:   no known conversion for argument 1 from 'char' to 'const std::error_code&'
  444 |   operator==(const error_code& __lhs, const error_code& __rhs) noexcept
      |              ~~~~~~~~~~~~~~~~~~^~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/system_error:460:3: note: candidate: 'bool std::operator==(const error_code&, const error_condition&)'
  460 |   operator==(const error_code& __lhs, const error_condition& __rhs) noexcept
      |   ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/system_error:460:32: note:   no known conversion for argument 1 from 'char' to 'const std::error_code&'
  460 |   operator==(const error_code& __lhs, const error_condition& __rhs) noexcept
      |              ~~~~~~~~~~~~~~~~~~^~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/system_error:475:3: note: candidate: 'bool std::operator==(const error_condition&, const error_condition&)'
  475 |   operator==(const error_condition& __lhs,
      |   ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/system_error:475:37: note:   no known conversion for argument 1 from 'char' to 'const std::error_condition&'
  475 |   operator==(const error_condition& __lhs,
      |              ~~~~~~~~~~~~~~~~~~~~~~~^~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/system_error:512:3: note: candidate: 'bool std::operator==(const error_condition&, const error_code&)'
  512 |   operator==(const error_condition& __lhs, const error_code& __rhs) noexcept
      |   ^~~~~~~~
/nix/store/1x1q5sqa0ilbi8fz7aayk02pjy5g7jhh-gcc-12.3.0/include/c++/12.3.0/system_error:512:37: note:   no known conversion for argument 1 from 'char' to 'const std::error_condition&'
  512 |   operator==(const error_condition& __lhs, const error_code& __rhs) noexcept
      |              ~~~~~~~~~~~~~~~~~~~~~~~^~~~~

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