1 files changed, 91 insertions, 0 deletions
diff --git a/src/parser.rs b/src/parser.rs
new file mode 100644
index 0000000..fe414b0
--- /dev/null
+++ b/src/parser.rs
@@ -0,0 +1,91 @@
+extern crate core;
+use core::str::Chars;
+
+#[derive(Debug, PartialEq)]
+pub enum Token {
+    Number(i32),
+    Plus,
+    Minus,
+    Multiply,
+    Divide,
+}
+
+pub struct Lexer<'a> {
+    chars: Chars<'a>,
+}
+
+impl<'a> Lexer<'a> {
+	// Constructor
+    pub fn new(input: &'a str) -> Self {
+        Lexer { chars: input.chars() }
+}
+
+	fn next_token(&mut self) -> Option<Token> {
+	        let next_char = self.chars.next()?;
+
+	        match next_char {
+	            '+' => Some(Token::Plus),
+	            '-' => Some(Token::Minus),
+	            '*' => Some(Token::Multiply),
+	            '/' => Some(Token::Divide),
+	            '1'..='9' => {
+	                let mut number = next_char.to_digit(10)? as i32;
+	                while let Some(next_char) = self.chars.clone().next() {
+	                    if let Some(digit) = next_char.to_digit(10) {
+	                        number = number * 10 + digit as i32;
+	                        self.chars.next();
+	                    } else {
+	                        break;
+	                    }
+	                }
+	                Some(Token::Number(number))
+	            }
+	            '0' => {
+	            	let base = match self.chars.next().unwrap() {
+	            		'b' => Some(2),
+	            		'o' => Some(8),
+	            		'x' => Some(16),
+	            		_   => None,
+	            	};
+	            	if base.is_none() {
+	            		return None;
+	            	}
+
+	            	let mut number = next_char.to_digit(base.clone().unwrap())?;
+	            	while let Some(next_char) = self.chars.clone().next() {
+	            		if let Some(digit) = next_char.to_digit(base.clone().unwrap()) {
+	            			number = number * base.clone().unwrap() + digit;
+	            			self.chars.next();
+	            		} else {
+	            			break;
+	            		}
+	            	}
+	            	Some(Token::Number(number as i32))
+	            }
+	            _ => None,
+	        }
+    }
+    
+    pub fn tokenize(&mut self) -> Vec<Token> {
+        let mut tokens = Vec::new();
+        while let Some(token) = self.next_token() {
+            tokens.push(token);
+        }
+        tokens
+    }
+}
+
+fn main() {
+    let mut lexer = Lexer::new("0x6A+0b001101*0o13");
+    let tokens = lexer.tokenize();
+    assert_eq!(
+    tokens,
+    vec![
+        Token::Number(106),
+        Token::Plus,
+        Token::Number(13),
+        Token::Multiply,
+        Token::Number(11),
+    ]
+    );
+}
+\ No newline at end of file