I've been tinkering for a while whit this problem, and hope someone gets what I'm Trying to do

I have an Xml file

<Results>
    <Details>
        <Id>1</Id>
    </Details>
    <StepResults>
        <Step SeqNr="1">
          <Value>10</Value
        </Step>
        <Step SeqNr="2">
          <Value>100</Value
        </Step>
    </StepResults>
</Results>

Now I created a script where people can parse this dynamically, lets say someone would like to get the id of this Result he can add a variable in their backend like so: [Details.Id] and this will be parsed in actionscript and get the result from the xml.

I parse it like this:

var pattern:RegExp = /\[[A-Za-z\.0-9()=\[\]@]*\]/g;
var possibleVars:Array = str.match(pattern);
for each(var myVar:String in possibleVars){
  //Remove the blockquotes from the var (this would be the [Details.Id])
  var checkVar:String = myVar.substr(1,(myVar.length-2));
  var result:String = dotSyntax(xmlToParse,checkVar);
}

private function dotSyntax(target:XML, path:String):String {
                    //Split the var into different pars
        var level:Array=path.split(".");
        var curr:* = target;
        for (var i:int = 0; i<level.length; i++) {

            if(i==0 && curr[level[i]].length() <= 0){
                return "";
                break;
            }

            //Try to go trough the xml with the supplied var
            curr=curr[level[i]];

        }
                    //return the value from the xml file (if all went well we have 1 here
        return curr;
    }

Now this really works like a charm, but I would like to give them the possibility to find values from the different steps, so normally to get this working in actionscript directly you would filter the xml like this (if you want the Value of step SeqNr=2):

resXml.StepResults.Step.(@SeqNr==2).Value

But I can't seem to get this to work with a dynamic variable. any pointers how I can do this using the dotSyntax function? (returning the value of step seqnr2)