peg-macros 0.6.0

Procedural macros for rust-peg. To use rust-peg, see the `peg` crate.
Documentation 
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//! Standalone version of rust-peg used for bootstrapping the meta-grammar

extern crate quote;
extern crate proc_macro2;
extern crate proc_macro;

use std::env;
use std::fs::File;
use std::io::{Read, Write};
use std::io::{stdin, stdout, stderr};
use std::path::Path;
use std::process;

// This can't use the `peg` crate as it would be a circular dependency, but the generated code in grammar.rs
// requires `::peg` paths.
extern crate peg_runtime as peg;

mod ast;
mod tokens;
mod grammar;
mod translate;
mod analysis;

fn main() {
	let args = env::args_os().collect::<Vec<_>>();
	let progname = &args[0];
	let mut log = stderr();

	let mut source = String::new();

	if args.len() == 2 && &args[1] != "-h" {
		File::open(Path::new(&args[1])).unwrap().read_to_string(&mut source).unwrap();
	} else if args.len() == 1 {
		stdin().read_to_string(&mut source).unwrap();
	} else {
		writeln!(log, "Usage: {} [file]", progname.to_string_lossy()).unwrap();
		process::exit(0);
	}

	let source_tokens = source.parse().expect("Error tokenizing input");
	let input_tokens = tokens::FlatTokenStream::new(source_tokens);
    let grammar = match grammar::peg::peg_grammar(&input_tokens) {
        Ok(g) => g,
        Err(err) => {
            eprintln!("Failed to parse grammar: expected {}", err.expected);
			process::exit(1);
        }
    };
	let parser_tokens = translate::compile_grammar(&grammar);
	let mut out = stdout();
	writeln!(&mut out, "// Generated by rust-peg. Do not edit.").unwrap();
	write!(&mut out, "{}", parser_tokens).unwrap();
}