pag_compiler/
lib.rs

1// Copyright (c) 2023 Paguroidea Developers
2//
3// Licensed under the Apache License, Version 2.0
4// <LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0> or the MIT
5// license <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
6// option. All files in the project carrying such notice may not be copied,
7// modified, or distributed except according to those terms.
8//! The compiler of Paguroidea. Designed for build scripts.
9use std::path::Path;
10
11use syn::File;
12
13/// Compile the grammar file at `input` to the parser source code
14/// at `output`.
15/// This function is designed to be used in `build.rs`. It will panic and
16/// output the reasons if any error occurs.
17pub fn compile<I: AsRef<Path>, O: AsRef<Path>>(input: I, output: O) {
18    use std::io::Write;
19    let data = std::fs::read_to_string(input.as_ref()).unwrap();
20    match pag_parser::generate_parser(&data) {
21        Ok(tokens) => {
22            let tree: File = syn::parse2(tokens).unwrap();
23            let prettified = prettyplease::unparse(&tree);
24            let mut file = std::fs::File::create(output.as_ref()).unwrap();
25            write!(
26                file,
27                "// This file is @generated by Paguroidea.\n\n{}",
28                prettified
29            )
30            .unwrap();
31            file.flush().unwrap();
32        }
33        Err(errs) => {
34            errs.report_stderr(&format!("{}", input.as_ref().display()), &data)
35                .unwrap();
36            panic!("failed to compile parser")
37        }
38    }
39}
pag_compiler/lib.rs

pag_compiler/
lib.rs
