add pratt parser

src/main.rs

@@ -3,6 +3,8 @@ use std::{fs::File, io::Read};
 mod token;
 mod lexer;
 use lexer::Lexer;
+mod parser;
+use parser::Parser;
 
 fn main() -> std::io::Result<()> {
     let args = std::env::args().collect::<Vec<String>>();
@@ -14,10 +16,20 @@ fn main() -> std::io::Result<()> {
 
     let mut lexer = Lexer::new(&source);
 
+    let mut tokens = Vec::new();
+    while let Some(tok) = lexer.next() {
+        print!("{tok:?}, ");
+        tokens.push(tok);
+    }
+
+    println!("\n");
+
+    let mut parser = Parser::new(tokens);
     loop {
-        match lexer.next() {
-            Some(tok) => print!("{tok:?}, "),
-            None => break
+        let parsed = parser.parse();
+        match parsed {
+            parser::Expr::EOL => break,
+            _ => println!("{:?}", parsed)
         }
     }