function getPrecedents(thisFormula){

var exp = /(w+!)?$?[A-Z]{1,}(?:d+)?(:?$?w+)*(?!()b/gm;
var results=[];
var result;



while ((result=exp.exec(thisFormula))!== null){
  if (!/^[A-Za-z]+$/.test(result[0]))
    results.push(result[0]); }
 return results;
}