从板条箱stdweb使用＃[JS_EXPORT]时会出现错误

Question

我需要在Rust-Wasm程序中读取客户端文件，并且我正在尝试使用Stackoverflow上的两个解决方案 and https://stackoverflow.com/a/a/a/69305956/444666255 。这两种解决方案均被接受并给予赏金，因此我假设它们起作用。

这两者都使用了以下代码，

use stdweb::js_export
#[js_export]

但是当我尝试编译这些代码时，我会遵循

error[E0425]: cannot find function `__web_free` in module `stdweb::private`
  --> src/lib.rs:14:1
   |
14 | #[js_export]
   | ^^^^^^^^^^^^ not found in `stdweb::private`
   |
   = note: this error originates in the attribute macro `js_export` (in Nightly builds, run with -Z macro-backtrace for more info)

错误的错误。我们如何使它起作用？

我从Stackoverflow https://stackoverflow.com/a/51231915

#[macro_use]
extern crate stdweb;

use stdweb::js_export;
use stdweb::web::FileReader;
use stdweb::web::FileReaderResult;

#[js_export]
fn print_result(file_reader: FileReader) -> String {
    match file_reader.result() {
        Some(value) => match value {
            FileReaderResult::String(value) => value,
            _ => String::from("not a text"),
        }
        None => String::from("empty")
    }
}

pub fn test_reader() {
    stdweb::initialize();

    stdweb::event_loop();
}

cargo.toml文件是

[package]
name = "read-file2"
version = "0.1.0"
authors = ["kushdesh"]
edition = "2018"

[lib]
crate-type = ["cdylib", "rlib"]

[features]
default = ["console_error_panic_hook"]

[dependencies]
wasm-bindgen = "0.2.63"
stdweb = "0.4.20"

console_error_panic_hook = { version = "0.1.6", optional = true }

wee_alloc = { version = "0.4.5", optional = true }

[dev-dependencies]
wasm-bindgen-test = "0.3.13"

[profile.release]
# Tell `rustc` to optimize for small code size.
opt-level = "s"