the implementation of `where` (or `filter`) would ...

# language-proposals

[groostav]

the implementation of where (or filter) would be something like:

fun filter(ast: LambdaExpression) : Iterable<Things>{
  //"LambdaExpression" is a C# type, see <https://msdn.microsoft.com/en-us/library/system.linq.expressions.lambdaexpression(v=vs.110).aspx>
  val queryHeader = "SELECT * FROM Customers WHERE";
  if(ast is Expression){
    val result = ast.getLeftChild().toString + ast.getOperator() + ast.getRightChild()
  }
  //...
  engine.run(queryHeader + result)
}