test program

src/lib.rs

@@ -5,5 +5,11 @@ mod parse;
 pub fn run_program(program: &str) {
     let lexer = lex::Lexer::lex(program);
     let tokens: Result<Vec<_>, _> = lexer.collect();
-    println!("{:#?}", tokens);
+    println!(
+        "{:#?}",
+        tokens.map(|tokens| tokens
+            .into_iter()
+            .map(|token| token.kind)
+            .collect::<Vec<_>>())
+    );
 }