cstd.crs

// Copper standard library — written in Copper itself.
// Loaded automatically when a program does `import { ... } from cstd`.
// The compiler wraps everything below in `pub mod cstd { ... }` and
// rewrites every `fn` into `pub fn` so user `use cstd::{X};` resolves.
//
// Functions that Copper's transpiler cannot yet express cleanly (multi-line
// method chains, raw `&[T]` slice types, `cfg!(target_os = ...)` macros)
// live in `std/cstd_native.rs` and are bundled alongside this module.

func String input(prompt: &str) {
    print!("{}", prompt)
    std::io::Write::flush(&mut std::io::stdout()).ok()
    mut buf = String::new()
    std::io::stdin().read_line(&mut buf).expect("failed to read stdin")
    return buf.trim_end().to_string()
}

func String readln() {
    mut buf = String::new()
    std::io::stdin().read_line(&mut buf).expect("failed to read stdin")
    return buf.trim_end().to_string()
}

func void exit(code: i32) {
    std::process::exit(code)
}

func void die(msg: &str) {
    eprintln!("{}", msg)
    std::process::exit(1)
}

func void sleep_ms(ms: u64) {
    std::thread::sleep(std::time::Duration::from_millis(ms))
}

func String env(name: &str) {
    return std::env::var(name).unwrap_or_default()
}

func bool exists(path: &str) {
    return std::path::Path::new(path).exists()
}

func bool is_file(path: &str) {
    return std::path::Path::new(path).is_file()
}

func bool is_dir(path: &str) {
    return std::path::Path::new(path).is_dir()
}

func String read_file(path: &str) {
    return std::fs::read_to_string(path).expect("read_file failed")
}

func void write_file(path: &str, content: &str) {
    std::fs::write(path, content).expect("write_file failed")
}

func String trim(s: &str) {
    return s.trim().to_string()
}

func void panic_if(cond: bool, msg: &str) {
    if cond {
        panic!("{}", msg)
    }
}