Androidstudio 运行 mod.rs文件一直报这个错误

[winnxiegang]

C:\Users\hp.cargo\registry\src\mirrors.ustc.edu.cn-61ef6e0cd06fb9b8\serde-1.0.152\src\private\ser.rs:294:9 | 294 | try!(state.serialize_field(self.tag, self.variant_name)); | -------------------------------------------------------- in this macro invocation | = note: this error originates in the macro try (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0425]: cannot find function, tuple struct or tuple variant Some in this scope --> C:\Users\hp.cargo\registry\src\mirrors.ustc.edu.cn-61ef6e0cd06fb9b8\serde-1.0.152\src\private\ser.rs:319:56 | 319 | let mut map = try!(self.delegate.serialize_map(Some(2))); | ^^^^ not found in this scope | help: consider importing one of these items | 1 + use __private::de::Content::Some; | 1 + use __private::ser::Content::Some; |

error[E0531]: cannot find tuple struct or tuple variant Ok in this scope --> C:\Users\hp.cargo\registry\src\mirrors.ustc.edu.cn-61ef6e0cd06fb9b8\serde-1.0.152\src\lib.rs:280:13 | 280 | Ok(val) => val, | ^^ not found in this scope | ::: C:\Users\hp.cargo\registry\src\mirrors.ustc.edu.cn-61ef6e0cd06fb9b8\serde-1.0.152\src\private\ser.rs:319:23 | 319 | let mut map = try!(self.delegate.serialize_map(Some(2))); | ------------------------------------------ in this macro invocation | = note: this error originates in the macro try (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0531]: cannot find tuple struct or tuple variant Err in this scope --> C:\Users\hp.cargo\registry\src\mirrors.ustc.edu.cn-61ef6e0cd06fb9b8\serde-1.0.152\src\lib.rs:281:13 | 281 | Err(err) => return Err(err), | ^^^ not found in this scope | ::: C:\Users\hp.cargo\registry\src\mirrors.ustc.edu.cn-61ef6e0cd06fb9b8\serde-1.0.152\src\private\ser.rs:319:23 | 319 | let mut map = try!(self.delegate.serialize_map(Some(2))); | -------