//crossjoin
//{A,B} join {C,D} -> {AC, AD, BD, BD}
public AcidCombination join(AcidCombination other)
{
return(new AcidCombination(list.SelectMany(x => other.list, (my, o) => my.add(o))));
}
public PrositeRegex(string regexRaw)
{
this.regexRaw = regexRaw;
elements = regexRaw.Split('-').Select(RepeatedAcid.createRepeatedAminoAcid).ToList();
acidCombinations = allAcidCombinations(elements);
}
