CreatePathSymbols.cs

private static SymbolTable CreatePathSymbols(SymbolTable symbols, IEnumerable<String> fragments)
{
    return EnumerableEx.Generate(
        Tuple.Create(fragments, symbols),
        _ => _.Item1.Any(),
        _ => Tuple.Create(_.Item1.Skip(1), _.Item1.First()
            .Let(f => _.Item2.ExistsKey(f) && _.Item2.Resolve(f).Const<SymbolTable>() != null
                ? symbols.Resolve(f).Const<SymbolTable>()
                : new SymbolTable().Apply(s => _.Item2[f] = Expression.Constant(s))
        )),
        _ => _.Item2
    ).Last().Resolve(fragments.Last()).Const<SymbolTable>();
}