Function call_closure_lazy 

fn call_closure_lazy(
    interp: &Interpreter,
    params: &[Param],
    body: &Expr,
    closure_env: &Environment,
    func: &RValue,
    positional: &[RValue],
    named: &[(String, RValue)],
    call_expr: Expr,
) -> Result<RValue, RFlow>

Call a closure with lazy (promise) arguments. Arguments are bound as RValue::Promise values in the call environment, only forced when accessed.