From: Mark Thom <markjordanthom@gmail.com>
Date: Tue, 5 Feb 2019 04:24:26 +0000 (-0700)
Subject: add support for copying attributed variables in copy_term
X-Git-Tag: v0.8.110~275
X-Git-Url: https://git.sagredo.dev/?a=commitdiff_plain;h=50dd3afaa853df44c5fe3c0bc137c94b18462c64;p=scryer-prolog.git

add support for copying attributed variables in copy_term
---

diff --git a/src/prolog/copier.rs b/src/prolog/copier.rs
index f5497529..f075640b 100644
--- a/src/prolog/copier.rs
+++ b/src/prolog/copier.rs
@@ -30,16 +30,26 @@ pub(crate) trait CopierTarget: IndexMut<usize, Output=HeapCellValue>
 
     fn reinstantiate_var(&mut self, ra: Addr, scan: usize, trail: &mut Trail)
     {
-        self[scan] = HeapCellValue::Addr(Addr::HeapCell(scan));
-
-        if let Addr::HeapCell(hc) = ra.clone() {
-            self[hc] = HeapCellValue::Addr(Addr::HeapCell(scan));
-            trail.push((Ref::HeapCell(hc),
-                        HeapCellValue::Addr(Addr::HeapCell(hc))));
-        } else if let Addr::StackCell(fr, sc) = ra {
-            self.stack()[fr][sc] = Addr::HeapCell(scan);
-            trail.push((Ref::StackCell(fr, sc),
-                        HeapCellValue::Addr(Addr::StackCell(fr, sc))));
+        match ra {
+            Addr::HeapCell(hc) => {
+                self[scan] = HeapCellValue::Addr(Addr::HeapCell(scan));
+                self[hc] = HeapCellValue::Addr(Addr::HeapCell(scan));
+                trail.push((Ref::HeapCell(hc),
+                            HeapCellValue::Addr(Addr::HeapCell(hc))));
+            },
+            Addr::StackCell(fr, sc) => {
+                self[scan] = HeapCellValue::Addr(Addr::HeapCell(scan));
+                self.stack()[fr][sc] = Addr::HeapCell(scan);
+                trail.push((Ref::StackCell(fr, sc),
+                            HeapCellValue::Addr(Addr::StackCell(fr, sc))));
+            },
+            Addr::AttrVar(hc) => {
+                self[scan] = HeapCellValue::Addr(Addr::AttrVar(scan));
+                self[hc] = HeapCellValue::Addr(Addr::AttrVar(scan));
+                trail.push((Ref::AttrVar(hc),
+                            HeapCellValue::Addr(Addr::AttrVar(hc))));
+            },
+            _ => {}
         }
     }
 
@@ -111,6 +121,12 @@ pub(crate) trait CopierTarget: IndexMut<usize, Output=HeapCellValue>
                                 },
                                 _ if ra == rd => {
                                     self.reinstantiate_var(ra, scan, &mut trail);
+
+                                    if let Addr::AttrVar(h) = rd {
+                                        let value = self[h + 1].clone();
+                                        self.push(value);
+                                    }
+
                                     scan += 1;
                                 },
                                 _ => self[scan] = HeapCellValue::Addr(rd)
diff --git a/src/prolog/machine/machine_state_impl.rs b/src/prolog/machine/machine_state_impl.rs
index 00e6bf18..0743b062 100644
--- a/src/prolog/machine/machine_state_impl.rs
+++ b/src/prolog/machine/machine_state_impl.rs
@@ -1588,7 +1588,7 @@ impl MachineState {
         for (v1, v2) in iter {
             match (v1, v2) {
                 (HeapCellValue::Addr(Addr::Lis(_)), HeapCellValue::Addr(Addr::Con(Constant::String(_))))
-                    | (HeapCellValue::Addr(Addr::Con(Constant::String(_))), HeapCellValue::Addr(Addr::Lis(_)))
+              | (HeapCellValue::Addr(Addr::Con(Constant::String(_))), HeapCellValue::Addr(Addr::Lis(_)))
                     if self.flags.double_quotes.is_chars() => {},
                 (HeapCellValue::Addr(Addr::Con(Constant::EmptyList)),
                  HeapCellValue::Addr(Addr::Con(Constant::String(ref s))))