Vendor things

third-party/vendor/winnow/examples/s_expression/main.rs

@@ -0,0 +1,20 @@
+//! In this example we build an [S-expression](https://en.wikipedia.org/wiki/S-expression)
+//! parser and tiny [lisp](https://en.wikipedia.org/wiki/Lisp_(programming_language)) interpreter.
+//! Lisp is a simple type of language made up of Atoms and Lists, forming easily parsable trees.
+
+#![cfg(feature = "alloc")]
+
+mod parser;
+
+fn main() {
+    let expression_1 = "((if (= (+ 3 (/ 9 3))
+         (* 2 3))
+     *
+     /)
+  456 123)";
+    println!(
+        "\"{}\"\nevaled gives us: {:?}",
+        expression_1,
+        parser::eval_from_str(expression_1)
+    );
+}