From a93fc48ee8a99a982976739892b4956f3d411b48 Mon Sep 17 00:00:00 2001
From: Greg Shuflin <greg.shuflin@protonmail.com>
Date: Sat, 13 Nov 2021 13:33:15 -0800
Subject: [PATCH] Make anciliary parsing functions not panic

---
 schala-lang/language/src/parsing/new.rs | 22 +++++++++-------------
 1 file changed, 9 insertions(+), 13 deletions(-)

diff --git a/schala-lang/language/src/parsing/new.rs b/schala-lang/language/src/parsing/new.rs
index 6ca0e04..134ef15 100644
--- a/schala-lang/language/src/parsing/new.rs
+++ b/schala-lang/language/src/parsing/new.rs
@@ -452,10 +452,10 @@ peg::parser! {
             digits:digits() { ExpressionKind::NatLiteral(digits.parse().unwrap()) }
 
         rule bin_literal() -> ExpressionKind =
-            "0b" digits:bin_digits() { ExpressionKind::NatLiteral(parse_binary(digits)) }
+            "0b" digits:bin_digits() {? parse_binary(digits).map(ExpressionKind::NatLiteral) }
 
         rule hex_literal() -> ExpressionKind =
-            "0x" digits:hex_digits() { ExpressionKind::NatLiteral(parse_hex(digits)) }
+            "0x" digits:hex_digits() {? parse_hex(digits).map(ExpressionKind::NatLiteral) }
 
         rule float_literal() -> ExpressionKind =
             ds:$( digits() "." digits()? / "." digits() ) { ExpressionKind::FloatLiteral(ds.parse().unwrap()) }
@@ -471,7 +471,7 @@ peg::parser! {
     }
 }
 
-fn parse_binary(digits: &str /*, tok: Token*/) -> u64 {
+fn parse_binary(digits: &str) -> Result<u64, &'static str> {
     let mut result: u64 = 0;
     let mut multiplier = 1;
     for d in digits.chars().rev() {
@@ -483,17 +483,13 @@ fn parse_binary(digits: &str /*, tok: Token*/) -> u64 {
         }
         multiplier = match multiplier.checked_mul(2) {
             Some(m) => m,
-            None =>
-            /*return ParseError::new_with_token("This binary expression will overflow", tok),*/
-                panic!(),
+            None => return Err("Binary expression will overflow"),
         }
     }
-    //Ok(result)
-    result
+    Ok(result)
 }
 
-//TODO fix these two functions
-fn parse_hex(digits: &str) -> u64 {
+fn parse_hex(digits: &str) -> Result<u64, &'static str> {
     let mut result: u64 = 0;
     let mut multiplier: u64 = 1;
     for d in digits.chars().rev() {
@@ -502,14 +498,14 @@ fn parse_hex(digits: &str) -> u64 {
         }
         match d.to_digit(16) {
             Some(n) => result += n as u64 * multiplier,
-            None => panic!(),
+            None => return Err("Internal parser error: invalid hex digit"),
         }
         multiplier = match multiplier.checked_mul(16) {
             Some(m) => m,
-            None => panic!(),
+            None => return Err("Hexadecimal expression will overflow"),
         }
     }
-    result
+    Ok(result)
 }
 
 #[derive(Debug)]