message: [crispy] base64: code cleanup
diff: #pragma once
  #include <string>
  +#include <string_view>
  namespace crispy::base64 {
  @@ -115,13 +116,15 @@ size_t decodeLength(Iterator begin, Iterator end, IndexTable const& index)
  {
  Iterator pos = begin;
  - while (pos != end && index[static_cast<size_t>(*pos)] <= 63)
  + auto const indexSize = std::size(index);
  +
  + while (pos != end && index[static_cast<size_t>(*pos)] < indexSize)
  pos++;
  - int nprbytes = std::distance(begin, pos) - 1;
  - int nbytesdecoded = ((nprbytes + 3) / 4) * 3;
  + int const nprbytes = std::distance(begin, pos) - 1;
  + int const nbytesdecoded = ((nprbytes + 3) / 4) * 3;
  - return nbytesdecoded + 1;
  + return nbytesdecoded;
  }
  template <typename Iterator>
  