From 229470fee3bf0946f9150f2460cd04cf3d603bbb Mon Sep 17 00:00:00 2001
From: Scott Richmond <kredati@users.noreply.github.com>
Date: Wed, 11 Dec 2024 19:11:40 -0500
Subject: [PATCH] refactor process to use `visit` method everywhere

---
 src/main.rs    |  7 ++++---
 src/process.rs | 37 ++++++++++---------------------------
 2 files changed, 14 insertions(+), 30 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 07ffbd7..9f8b18d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -182,9 +182,10 @@ pub fn run(src: &'static str) {
 
 pub fn main() {
     let src = "
-when {
-    false -> :false
-    true -> :true
+let guard = :nil
+match :foo with {
+    :foo if guard -> :guarded
+    _ -> :unguarded
 }
     ";
     run(src);
diff --git a/src/process.rs b/src/process.rs
index 39a618e..8a9cf7d 100644
--- a/src/process.rs
+++ b/src/process.rs
@@ -60,12 +60,6 @@ impl<'src> Process<'src> {
         self.locals.push((word, value.clone()));
     }
 
-    pub fn pop_to(&mut self, n: usize) {
-        while self.locals.len() > n {
-            self.locals.pop();
-        }
-    }
-
     pub fn match_eq<T>(&self, x: T, y: T) -> Option<&Process<'src>>
     where
         T: PartialEq,
@@ -134,7 +128,7 @@ impl<'src> Process<'src> {
                         let list = Value::List(list);
                         self.match_pattern(&patt.0, &list);
                     } else if self.match_pattern(&x[i].0, &y[i]).is_none() {
-                        self.pop_to(to);
+                        self.locals.truncate(to);
                         return None;
                     }
                 }
@@ -151,7 +145,7 @@ impl<'src> Process<'src> {
                         let list = Value::List(y.skip(i));
                         self.match_pattern(&patt.0, &list);
                     } else if self.match_pattern(patt, y.get(i).unwrap()).is_none() {
-                        self.pop_to(to);
+                        self.locals.truncate(to);
                         return None;
                     }
                 }
@@ -172,7 +166,7 @@ impl<'src> Process<'src> {
                         PairPattern(key, patt) => {
                             if let Some(val) = y.get(key) {
                                 if self.match_pattern(&patt.0, val).is_none() {
-                                    self.pop_to(to);
+                                    self.locals.truncate(to);
                                     return None;
                                 } else {
                                     matched.push(key);
@@ -210,31 +204,23 @@ impl<'src> Process<'src> {
         clauses: &'src [Spanned<Ast>],
     ) -> LResult<'src> {
         {
-            let parent = self.ast;
+            let root = self.ast;
             let to = self.locals.len();
             let mut clauses = clauses.iter();
             while let Some((Ast::MatchClause(patt, guard, body), _)) = clauses.next() {
                 if self.match_pattern(&patt.0, value).is_some() {
                     let pass_guard = match guard.as_ref() {
                         None => true,
-                        Some((ast, _)) => {
-                            self.ast = ast;
-                            let guard_res = self.eval();
-                            match &guard_res {
-                                Err(_) => return guard_res,
-                                Ok(val) => val.bool(),
-                            }
-                        }
+                        Some(guard_expr) => self.visit(guard_expr)?.bool(),
                     };
                     if !pass_guard {
-                        self.pop_to(to);
+                        self.locals.truncate(to);
                         continue;
                     }
-                    self.ast = &body.0;
-                    let res = self.eval();
-                    self.pop_to(to);
-                    self.ast = parent;
-                    return res;
+                    let result = self.visit(body);
+                    self.locals.truncate(to);
+                    self.ast = root;
+                    return result;
                 }
             }
             Err(LErr::new("no match".to_string()))
@@ -467,9 +453,6 @@ impl<'src> Process<'src> {
             Fn(name, clauses, doc) => {
                 let doc = doc.map(|s| s.to_string());
                 let ptr: *const Ast = root_node;
-                // dbg!(&root);
-                // dbg!(&ptr);
-                // dbg!(&self.fn_info);
                 let info = self.fn_info.get(&ptr).unwrap();
                 let FnInfo::Defined(_, _, enclosing) = info else {
                     unreachable!()