Syn parser

Cargo.toml

[package]
name = "hello_rust"
version = "0.1.0"
authors = ["AchalaSB <achalasbhatt@gmail.com>"]
edition = "2018"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
syn = {version = "0.13", features = ["full", "extra-traits"] }

main.rs

fn main() {
    println!("Hello, world!");
}

syn.rs

extern crate syn;

use std::env;
use std::fs::File;
use std::io::Read;

fn main() {
    let mut args = env::args();
    args.next();

    match args.next() {
        Some(fname) => {
            let mut src = String::new();
            let mut file = File::open(&fname).expect("Unable to open file");
            file.read_to_string(&mut src).expect("Unable to read file");

            let syntax = syn::parse_file(&src).expect("Unable to parse file");
            println!("{:#?}", syntax);
        }
        _ => {
            println!("Please supply the file to compile");
        }
    }
}