School Locations Sorter

var locationSorter = function(a, b) {
    // this sorts letters before numbers on the 1st character, and also
    // sorts something like "1C9" before "1C11"
    
    var n = (a.name || "").toLowerCase();
		var m = (b.name || "").toLowerCase();
  
    var l = Math.min(n.length, m.length);
    if (n.substr(0, l) === m.substr(0,l)) {
      return (n.length - m.length);
    }
    
    for (var i = 0; i < l; i++) {
      var nChar = n.charCodeAt(i);
      var mChar = m.charCodeAt(i);
      
      var nCharIsDigit = (nChar >= 48 && nChar <= 57);
      var mCharIsDigit = (mChar >= 48 && mChar <= 57);
      var nCharIsLetter = (nChar >= 97 && nChar <= 122);
      var mCharIsLetter = (mChar >= 97 && mChar <= 122);
      
      if (i === 0) {
        // for 1st character, letters are sorted before numbers
        if (nCharIsDigit && mCharIsLetter) {
          return 1; 
        }
        if (nCharIsLetter && mCharIsDigit) {
          return -1;
        }
      }
      else if (i > 0 && nCharIsDigit && mCharIsDigit) {
        // Compare numerical values
        var numberComparison =  parseInt(n.substr(i), 10) - parseInt(m.substr(i), 10);
        if (numberComparison !== 0) return numberComparison; 
        // note: if numberComparison = 0, we might be comparing something like "1CD" and "1FF",
        //       so check the next character instead
      }
      
      if (nChar !== mChar) {
        return nChar - mChar;
      }

    }    
  };