# cmd_lib - Rust command line library
Common rust command line macros and utils, to write shell script like tasks
easily in rust programming language.
## run_cmd! --> CmdResult
```rust
let name = "rust";
run_cmd!("echo hello, {}", name);
// pipe commands are also supported
run_cmd!("du -ah . | sort -hr | head -n 10");
// also work without string quote
run_cmd!(du -ah . | sort -hr | head -n 10);
// or a group of commands
// if any command fails, just return Err(...)
if run_cmd! {
ls / | wc -w
echo "bad cmd"
ls -l /nofile
date
}.is_err() {
warn!("Run group command failed");
}
```
## run_fun! --> FunResult
```rust
let version = run_fun!("rustc --version")?;
info!("Your rust version is {}", version.trim());
// with pipes
let n = run_fun!("echo the quick brown fox jumped over the lazy dog | wc -w")?;
info!("There are {} words in above sentence", n.trim());
```
## Easy Reporting
```rust
info!("Running command xxx ...");
warn!("Running command failed");
err!("Copying failed");
die!("Command exit unexpectedly: {}", reason);
```
output:
```bash
INFO: Running command xxx ...
WARN: Running command failed
ERROR: Copying file failed
FATAL: Command exit unexpectedly: disk is full
```
## Complete Example
```rust
use cmd_lib::{info, warn, output, run_cmd, run_fun, CmdResult, FunResult};
fn foo() -> CmdResult {
run_cmd!("sleep 3")?;
run_cmd!("ls /nofile")?;
Ok(())
}
fn get_year() -> FunResult {
let year = run_fun!("date +%Y")?;
output!("{}", year.trim())
}
fn main() -> CmdResult {
let result = run_fun!("du -ah . | sort -hr | head -n 5")?;
info!("Top 5 directories:\n{}", result.trim());
if foo().is_err() {
warn!("Failed to run foo()");
}
if get_year()? == "2019" {
info!("You are in year 2019");
} else {
info!("Which year are you in ?");
}
Ok(())
}
```
output:
```bash
5.1M .
2.7M ./main
2.4M ./main2
8.0K ./lib.rs
4.0K ./main.rs
INFO: Running "sleep 3" ...
INFO: Running "ls /nofile" ...
ls: cannot access '/nofile': No such file or directory
WARN: Failed to run foo()
INFO: Running "date +%Y" ...
INFO: You are in year 2019
```
## Related
See [rust-shell-script](https://github.com/rust-shell-script/rust-shell-script/), which can compile
rust-shell-script scripting language directly into rust code.