fork download 
  1. bool nectar_loader::next_token(string& token,
  2.                                const set<char>& special_characters)
  3. {
  4.     // TODO: test the *full* hell out of this function
  5.     // FIXME: ugly as hell, alternatives welcome.
  6.     token.clear();
  7.     bool inside_quotes = false;
  8.     char c;
  9.     auto add_char = [&]
  10.     {
  11.         token.append(1, c);
  12.     };
  13.     while(m_stream.get(c))
  14.     {
  15.         debug(debug::lexer) << "nectar_loader::next_token::line number " << m_line_number << ", character: \'" << output_form(c) << "\', token so far: "
  16.                             << output_form(token) << "\n";
  17.         if(inside_quotes)
  18.         {
  19.             debug(debug::lexer) << "nectar_loader::next_token::Inside quotes.\n";
  20.             if('\"' == c)
  21.             {
  22.                 break;    // end of token at end of quotes
  23.             }
  24.             else if('\n' == c)
  25.             {
  26.                 throw syntax_error("Quoted strings cannot span several lines.", m_filename, m_line_number);
  27.             }
  28.             else if(token.empty() && std::isspace(c, m_stream.getloc()))
  29.             {
  30.                 throw syntax_error("Beginning quote must not be followed by a whitespace.", m_filename, m_line_number);
  31.             }
  32.             else
  33.             {
  34.                 add_char();
  35.             }
  36.         }
  37.         else
  38.         {
  39.             if(token.empty())
  40.             {
  41.                 if('\n' == c)
  42.                 {
  43.                     ++m_line_number;
  44.                 }
  45.  
  46.                 if(contains(special_characters, c))
  47.                 {
  48.                     // special characters are tokens of their own
  49.                     debug(debug::lexer) << "nectar_loader::next_token::Detected special character.\n";
  50.                     token.append(1, c);
  51.                     return true;
  52.                 }
  53.                 else if('\"' == c)
  54.                 {
  55.                     debug(debug::lexer) << "nectar_loader::next_token::Quote detected.\n";
  56.                     inside_quotes = true;
  57.                     continue;
  58.                 }
  59.                 else if(std::isspace(c, m_stream.getloc()))
  60.                 {
  61.                     continue;
  62.                 }
  63.                 else if('#' == c)
  64.                 {
  65.                     // skip over comments
  66.                     debug(debug::lexer) << "nectar_loader::next_token::Skipping over comments.\n";
  67.                     string temp;
  68.                     std::getline(m_stream, temp);
  69.                     m_stream.putback('\n');
  70.                 }
  71.                 else if('\\' == c)
  72.                 {
  73.                     string temp;
  74.                     std::getline(m_stream, temp);
  75.                     ++m_line_number;
  76.                 }
  77.                 else
  78.                 {
  79.                     add_char();
  80.                 }
  81.             }
  82.             else if(std::isspace(c, m_stream.getloc()) || contains(special_characters, c))
  83.             {
  84.                 // special characters or whitespace seperate tokens
  85.                 debug(debug::lexer) << "nectar_loader::next_token::Detected special character or space.\n";
  86.                 m_stream.putback(c);
  87.                 break;
  88.             }
  89.             else if('\"' == c)
  90.             {
  91.                 throw syntax_error("Beginning quotes must be preceded by a whitespace or a special character.", m_filename, m_line_number);
  92.                 return false;
  93.             }
  94.             else
  95.             {
  96.                 add_char();
  97.             }
  98.         }
  99.     }
  100.     if(!token.empty())
  101.     {
  102.         debug(debug::lexer) << "nectar_loader::next_token:Token extracted: \'" << output_form(token) << "\'\n";
  103.     }
  104.  
  105.     return !token.empty();
  106. }
  107.  
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin 
Standard input is empty
compilation info 
prog.cpp:1: error: ‘nectar_loader’ has not been declared
prog.cpp:1: error: ‘string’ was not declared in this scope
prog.cpp:1: error: ‘token’ was not declared in this scope
prog.cpp:2: error: expected primary-expression before ‘const’
prog.cpp:2: error: initializer expression list treated as compound expression
prog.cpp:3: error: expected ‘,’ or ‘;’ before ‘{’ token
stdout 
Standard output is empty
https://ideone.com/jVGg6
language:
C++ (gcc 8.3)
created:
11 years ago
visibility:
secret

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!