Preserve static value in recursive macro

[shirleyquirk]

Something liiike 
    
    
    import tables
    type
      Obj = ref object
        children: Table[string, Obj]
        value: string
    proc newObj():Obj=
      result = new Obj
      result.children=initTable[string, Obj]()
    proc newObj(key:string,kids:Obj=newObj()):Obj=
      result = new Obj
      result.children={key:kids}.toTable()
    proc `[]=`(o:Obj,k:string,val:string)=
      o.children[k].value=val
    proc `[]`(o:Obj,k:string):Obj=
      o.children[k]
    var rootobj = newObj("me",newObj("location",newObj("city")))
    rootobj["me"]["location"]["city"]="Toledo"
    
    
    proc getField(parent:Obj,f:seq[string]):string=
      if f.len==1:
        return parent[f[0]].value
      else:
        return getField(parent[f[0]],f[1..^1])
    
    echo getField(rootobj,@["me","location","city"])
    
    
    Run