transition to l3

src/l3/or_stack.rs

@@ -0,0 +1,112 @@
+use l3::ast::*;
+
+use std::ops::{Index, IndexMut};
+use std::vec::Vec;
+
+pub struct Frame {
+    pub global_index: usize,
+    pub e: usize,
+    pub cp: CodePtr,
+    pub b: usize,
+    pub bp: CodePtr,
+    pub tr: usize,
+    pub h: usize,
+    args: Vec<Addr>
+}
+
+impl Frame {
+    fn new(global_index: usize,
+           e: usize,
+           cp: CodePtr,
+           b: usize,
+           bp: CodePtr,
+           tr: usize,
+           h: usize,
+           n: usize)
+           -> Self
+    {
+        Frame {
+            global_index: global_index,
+            e: e,
+            cp: cp,
+            b: b,
+            bp: bp,
+            tr: tr,
+            h: h,
+            args: vec![Addr::HeapCell(0); n]
+        }
+    }
+
+    pub fn num_args(&self) -> usize {
+        self.args.len()
+    }
+}
+
+pub struct OrStack(Vec<Frame>);
+
+impl OrStack {
+    pub fn new() -> Self {
+        OrStack(Vec::new())
+    }
+
+    pub fn push(&mut self,
+                global_index: usize,
+                e: usize,
+                cp: CodePtr,
+                b: usize,
+                bp: CodePtr,
+                tr: usize,
+                h: usize,
+                n: usize)
+    {
+        self.0.push(Frame::new(global_index, e, cp, b, bp, tr, h, n));
+    }
+
+    pub fn len(&self) -> usize {
+        self.0.len()
+    }
+
+    pub fn clear(&mut self) {
+        self.0.clear()
+    }
+
+    pub fn top(&self) -> Option<&Frame> {
+        self.0.last()
+    }
+
+    pub fn pop(&mut self) {
+        self.0.pop();
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.0.is_empty()
+    }
+}
+
+impl Index<usize> for OrStack {
+    type Output = Frame;
+
+    fn index(&self, index: usize) -> &Self::Output {
+        self.0.index(index)
+    }
+}
+
+impl IndexMut<usize> for OrStack {
+    fn index_mut(&mut self, index: usize) -> &mut Self::Output {
+        self.0.index_mut(index)
+    }
+}
+
+impl Index<usize> for Frame {
+    type Output = Addr;
+
+    fn index(&self, index: usize) -> &Self::Output {
+        self.args.index(index - 1)
+    }
+}
+
+impl IndexMut<usize> for Frame {
+    fn index_mut(&mut self, index: usize) -> &mut Self::Output {
+        self.args.index_mut(index - 1)
+    }
+}