A fairly major refactor / simplification.

src/syntax.rs

@@ -1,14 +1,16 @@
+use codespan_reporting::files::SimpleFiles;
 use lalrpop_util::lalrpop_mod;
 use logos::Logos;
 
 mod location;
+mod simplify;
 mod tokens;
 lalrpop_mod!(
     #[allow(clippy::just_underscores_and_digits)]
     parser,
     "/syntax/parser.rs"
 );
-mod ast;
+pub mod ast;
 
 pub use crate::syntax::ast::*;
 pub use crate::syntax::location::Location;
@@ -17,14 +19,24 @@ pub use crate::syntax::tokens::{LexerError, Token};
 use lalrpop_util::ParseError;
 #[cfg(test)]
 use std::str::FromStr;
+use thiserror::Error;
 
-#[derive(Debug)]
+#[derive(Debug, Error)]
 pub enum ParserError {
+    #[error("Invalid token")]
     InvalidToken(Location),
+    #[error("Unrecognized EOF")]
     UnrecognizedEOF(Location, Vec<String>),
+    #[error("Unrecognized token")]
     UnrecognizedToken(Location, Location, Token, Vec<String>),
+    #[error("Extra token")]
     ExtraToken(Location, Token, Location),
+    #[error("Lexing failure")]
     LexFailure(Location),
+    #[error("File database error")]
+    FileDatabaseError(#[from] codespan_reporting::files::Error),
+    #[error("Read error")]
+    ReadError(#[from] std::io::Error),
 }
 
 impl ParserError {
@@ -62,6 +74,16 @@ impl ParserError {
 }
 
 impl Program {
+    pub fn parse_file(
+        file_database: &mut SimpleFiles<String, String>,
+        file_name: &str,
+    ) -> Result<Self, ParserError> {
+        let file_contents = std::fs::read_to_string(file_name)?;
+        let file_handle = file_database.add(file_name.to_string(), file_contents);
+        let file_db_info = file_database.get(file_handle)?;
+        Program::parse(file_handle, file_db_info.source())
+    }
+
     pub fn parse(file_idx: usize, buffer: &str) -> Result<Program, ParserError> {
         let lexer = Token::lexer(buffer)
             .spanned()