Cargo

Useful additional commands

• cargo install cargo-check (The command allows you to check the code, without build)
• cargo install cargo-edit (The command allows you to manage dependencies[add, rm, list].)
• cargo install cargo-graph (The command generates a dependency graph in GraphViz format.) cargo graph > deps.dot && cargo graph > deps.dot && dot deps.dot -Tpng -o deps.png
• cargo install cargo-watch (The command allows you to automatically collect code when changes are made to files.)
• cargo install cargo-count (The command allows you to calculate useful statistics about your code.)
• cargo install rustfmt (The command allows you to automatically format the code.)

Source code

How to return &str from a function?

use &'static str:

fn find_number(val: i32) -> &'static str {
    match val {
        7 => "seven",
        8 => "eight",
        _ => unreachable!(),
    }
}

How to print stack trace?

use std::fs::File;  
n main()  
{  
   let f = File::open("vector.txt");  
   match f   
   {  
       Ok(file) => file,  
       Err(error) => {  
       panic!("There was a problem opening the file: {:?}", error)  
     },  
   };

How do I print the type of a variable?

#![feature(core_intrinsics)]

fn print_type_of<T>(_: &T) {
   println!("{}", unsafe { std::intrinsics::type_name::<T>() });
}

fn main() {
   print_type_of(&32.90);          // prints "f64"
   print_type_of(&vec![1, 2, 4]);  // prints "std::vec::Vec<i32>"
   print_type_of(&"foo");          // prints "&str"
}