code: function evaluate(expr) {
              if (expr.substring(0, 2) === '==') {
                  return 'write(JSON.stringify('+expr.substring(2).trim()+'));\n';
              } else if (expr.substring(0, 1) === '=') {
                  return 'write('+expr.substring(1).trim()+');\n';
              } else if (expr.substring(0, 3) === '...') {
                  expr = '//...\n'+expr.substring(3).trim()+'\n//.';
              }
              if (expr !== '') {
                  return expr+'\n';
              }
              return '';
          }
docs: Evaluates a meta expression