From 7c6ea56df454739bf750a076c17c643f686cd875 Mon Sep 17 00:00:00 2001
From: Gabriel <68819302+obsidianical@users.noreply.github.com>
Date: Fri, 28 Jan 2022 22:38:44 +0100
Subject: [PATCH] aaa

---
 src/error.rs         | 28 ++++++++++++++++++++++++++++
 src/main.rs          |  1 +
 src/parsing/lexer.rs | 23 +++++++++++++----------
 3 files changed, 42 insertions(+), 10 deletions(-)

diff --git a/src/error.rs b/src/error.rs
index e69de29..2559f8e 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -0,0 +1,28 @@
+pub struct Position {
+    pub line: u32,
+    pub character: usize
+}
+
+pub struct IllegalCharacterError {
+    pub pos: Position,
+    pub cause: char,
+}
+
+trait Error {
+    fn make_msg(&self) -> String;
+}
+
+impl IllegalCharacterError {
+    pub fn new(pos: Position, chara: char) -> IllegalCharacterError {
+        IllegalCharacterError {
+            pos,
+            cause: chara
+        }
+    }
+}
+
+impl Error for IllegalCharacterError {
+    fn make_msg(&self) -> String {
+        String::from(format!("IllegalCharacterError at {}, {}: Unknown character '{}'", self.pos.line, self.pos.character % self.pos.line as usize, self.cause))
+    }
+}
diff --git a/src/main.rs b/src/main.rs
index 60a9c2c..77cb940 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,6 +3,7 @@ use std::fs;
 
 pub mod shell;
 pub mod parsing;
+pub mod error;
 
 use parsing::preprocessor::preprocess;
 
diff --git a/src/parsing/lexer.rs b/src/parsing/lexer.rs
index cf779f1..66d1e5e 100644
--- a/src/parsing/lexer.rs
+++ b/src/parsing/lexer.rs
@@ -1,5 +1,6 @@
 use super::preprocessor::preprocess;
 use super::token::Token;
+use crate::error::{IllegalCharacterError, Position};
 
 const DIGITS: &str = "0123456789";
 const ALPHABET: &str = "abcdefghijklmnopqrstuvwxyz";
@@ -7,26 +8,28 @@ const ALPHABET_C: &str = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
 
 pub struct Lexer {
     code: String,
-    pos: usize,
-    current: Option<char>,
+    pos: Position,
+    current: char,
 }
 
 impl Lexer {
     pub fn new(code: String) -> Lexer {
         Lexer {
             code: code.clone(),
-            pos: 0,
+            pos: Position { line: 0, character: 0 },
             current: code.chars().nth(0),
         }
     }
 
     pub fn next(&mut self) {
-        self.pos += 1;
-        self.current = if self.pos < self.code.len() {
-            self.code.chars().nth(self.pos)
-        } else {
-            None
-        };
+        self.pos.character += 1;
+        self.current = switch self.code.chars().nth(self.pos.character) {
+            Some(c) => {
+                let chara = ;
+                if chara == '\n' { self.pos.line += 1; };
+                chara
+            },
+            None => {}
     }
 
     pub fn tokenize(&mut self) -> Vec<Token> {
@@ -55,7 +58,7 @@ impl Lexer {
                         jump_next = true;
                         Some(self.make_nr_token())
                     } else {
-                        None
+                        IllegalCharacterError::new()
                     }
                 },
             };