`RUST_LOG=trace cargo test -- --nocapture`

use swc_core::ecma::{ast::Ident, visit::VisitMut};
use tracing::debug;

pub struct Whatplatform;

impl VisitMut for Whatplatform {
    // Implement necessary visit_mut_* methods for actual custom transform.
    // A comprehensive list of possible visitor methods can be found here:
    // https://rustdoc.swc.rs/swc_ecma_visit/trait.VisitMut.html
    fn visit_mut_ident(&mut self, n: &mut Ident) {
        debug!("Values: {:#?}", n);
    }
}

marcos

• https://kaisery.github.io/trpl-zh-cn/ch19-06-macros.html?search=hong
• https://blog.logrocket.com/macros-in-rust-a-tutorial-with-examples/

attach codes to function and struct, just like inherit

test single file

cargo test --all no_document_write_valid -- --nocapture

• no_document_write_valid test function name
• nocapture enable print

npm package rust app

https://blog.woubuc.be/post/publishing-rust-binary-on-npm/

看 demo 例子更加实时

brew package rust app / 打包 rust 到 homebrew

https://federicoterzi.com/blog/how-to-publish-your-rust-project-on-homebrew/

create rust lib

create a rust lib package

cargo new --lib <path>

build

cargo fmt
cargo build

找到编译后的可执行文件

in `target/debug/<pkg.name>`

开启某些 `package` 的 `feature` 编译。以便使用只有在这些 `feature` 下才能使用的功能。

// cargo.toml
[dependencies]
swc_common = { version = "0.10.9", features = ["tty-emitter"] }

enable feature

// in cargo.toml
[dependencies]
swc_common = { version = "0.10.9", features = ["tty-emitter"] }

tips

1. `cargo build --release` 的编译结果执行速度要快于 `cargo build` 的编译结果的执行速度

in `~/.cargo/config`

如果出现其中一个失败，轻尝试切换另外一个，如果都失败了，那么请清空`~/.cargo/config`内的文件，使用官方缘

use tsinghua

[source.crates-io]
replace-with = 'tuna'

[source.tuna]
registry = "https://mirrors.tuna.tsinghua.edu.cn/git/crates.io-index.git"

use ustc

[source.crates-io]
replace-with = 'ustc'

[source.ustc]
registry = "git://mirrors.ustc.edu.cn/crates.io-index"

一次性代理设置

RUSTUP_DIST_SERVER=https://mirrors.tuna.tsinghua.edu.cn/rustup rustup target add wasm32-unknown-unknown

refs: https://mirrors.tuna.tsinghua.edu.cn/help/rustup/

let ref s = SomeStruct {}
// 等价
let s = &SomeStructVariable

前者在一些 `Some` 配合使用时，可以避免一些类型问题

如果 `clone` 是个 `Option<T>`。更新内部 `field` 可通过以下方式

if let Some(ref mut c) = clone {
  c.enlarge(saved.unwrap().hi, hi);
}

mut field value / 让 struct 内的元素可修改

struct Token {
  position: uszie,
}

impl Token {
  fn next(&mut self) -> usize {
    self.position = self.position + 1
    self.position
  }
}

fn main() {
  let position = 1;
  let mut token = { position };
  token.next();
}

when

`#![feature] may not be used on the stable release channel`

try

cargo install nightly

then

rustup run nightly wasm-pack build --target web --out-name wasm --out-dir ./static

`--target web --out-name wasm --out-dir ./static` is optional

refs: https://github.com/rustwasm/wasm-pack/issues/629#issuecomment-488051800