anchor.diff:      eof = pe;
       
       assert(*pe == '\0' && "pointer does not end on NULL");
  -    assert(pe - p == len && "pointers aren't same distance");
       
       %% write init;
       %% write exec;
  
positive.code:   size_t next_keyword_start;
    size_t content_start;
    size_t content_end;
    size_t field_len;
    size_t query_start;
    size_t last_newline;
    size_t final_newline;
  
negative.code:   lexer->content_end = 0;
    lexer->content_len = 0;
    lexer->mark = 0;
    lexer->keyword_start = 0;
    lexer->keyword_end = 0;
    lexer->next_keyword_start = 0;
  