“预期的struct Foo，找到了另一个struct Foo”是什么意思？

我正在尝试构建HTML网络抓取工具，并且遇到了无法逾越的障碍。

#![feature(libc)]
#![feature(rustc_private)]
extern crate libc;

extern crate url;
extern crate hyper;
extern crate html5ever;
extern crate serialize;
extern crate html5ever_dom_sink;

#[macro_use]
extern crate tendril;

use tendril::{StrTendril, SliceExt};
use std::ffi::{CStr,CString};
use tendril::{ByteTendril, ReadExt};
use html5ever::{parse, one_input};
use html5ever_dom_sink::common::{Document, Doctype, Text, Comment, Element};
use html5ever_dom_sink::rcdom::{RcDom, Handle};

use hyper::Client;
use hyper::header::Connection;
use std::io::Read;

fn get_page(url: &str) -> String {
    let mut client = Client::new();
    let mut res = client.get(url)
       // set a header
       .header(Connection::close())
       // let 'er go!
       .send().unwrap();

    let mut body = String::new();
    res.read_to_string(&mut body).unwrap();

    body
}

#[no_mangle]
pub extern fn parse_page(url: *const libc::c_char) {
  let url_cstr = unsafe { CStr::from_ptr(url) };  // &std::ffi::c_str::CStr
  let url_and_str = url_cstr.to_str().unwrap();  // &str

  let body = get_page(url_and_str);

  let body_tendril = body.to_tendril();
  let body_tendril = body_tendril.try_reinterpret().unwrap();

  let dom: RcDom = parse(one_input(body_tendril), Default::default());


  // let c_body = CString::new(body).unwrap();  // std::ffi::c_str::CString

  // c_body.into_ptr()
}

当我用这个库构建cargo时，出现错误：

error: type mismatch resolving `<core::option::IntoIter<tendril::tendril::Tendril<_>> as core::iter::Iterator>::Item == tendril::tendril::Tendril<tendril::fmt::UTF8>`:
expected struct `tendril::tendril::Tendril`,
found a different struct `tendril::tendril::Tendril` 

如何将琴弦转换成正确的解析形式的卷须呢？