Boot_Banner/
lib.rs

1extern crate proc_macro;
2extern crate quote;
3extern crate syn;
4
5use proc_macro::TokenStream;
6use quote::quote;
7use syn::{
8    parse_macro_input, 
9    ItemFn
10};
11
12#[proc_macro_attribute]
13pub fn init(_attr: TokenStream, item: TokenStream) -> TokenStream {
14    let input = parse_macro_input!(item as ItemFn);
15
16    let name = &input.sig.ident;
17    let block = &input.block;
18
19    let gen = quote! {
20        fn #name() {
21            use std::env;
22            use std::fs;
23            use std::path::PathBuf;
24
25            // Attempt to read the banner content
26            let banner_content = (|| -> Result<String, Box<dyn std::error::Error>> {
27                let current_dir = env::current_dir()?;
28                let dir = current_dir.to_str().ok_or("Failed to convert directory path")?.to_string();
29                let file_path = PathBuf::from(&dir).join("banner.txt");
30                let file_nm = file_path.to_str().ok_or("Failed to convert file path")?;
31                let contents = fs::read_to_string(file_nm)?;
32                Ok(contents)
33            })();
34
35            // Match on the result of reading the banner content
36            match banner_content {
37                Ok(contents) => println!("{}", contents), // Print the banner if successful
38                Err(e) => eprintln!("Failed to load banner: {}", e), // Print error message if failed
39            }
40
41            // Execute the original function body
42            #block
43        }
44    };
45    gen.into()
46}
Boot_Banner/lib.rs

Boot_Banner/
lib.rs
