platform.js
function getOS(guesses) {
      return reduce(guesses, function(result, guess) {
        var pattern = guess.pattern || qualify(guess);
        if (!result && (result =
              RegExp('\\b' + pattern + '(?:/[\\d.]+|[ \\w.]*)', 'i').exec(ua)
            )) {
          result = cleanupOS(result, pattern, guess.label || guess);
        }
        return result;
      });
    }
function getOS(guesses) {
      return reduce(guesses, function(result, guess) {
        var pattern = guess.pattern || qualify(guess);
        if (!result && (result =
              RegExp('\\b' + pattern + '(?:/[\\d.]+|[ \\w.]*)', 'i').exec(ua)
            )) {
          result = cleanupOS(result, pattern, guess.label || guess);
        }
        return result;
      });
    }
function getOS ( guesses ) { return reduce ( guesses , function ( result , guess ) { var pattern = guess . pattern || qualify ( guess ) ; if ( ! result && ( result = RegExp ( '\\b' + pattern + '(?:/[\\d.]+|[ \\w.]*)' , 'i' ) . exec ( ua ) ) ) { result = cleanupOS ( result , pattern , guess . label || guess ) ; } return result ; } ) ; }
Picks the OS name from an array of guesses.

@private
@param {Array} guesses An array of guesses.
@returns {null|string} The detected OS name.
Picks the OS name from an array of guesses .