Fix

raviqqe · Dec 31, 2024 · 89ec972 · 89ec972
1 parent fc24ba1
commit 89ec972
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Showing 2 changed files with 20 additions and 10 deletions.
diff --git a/r7rs/src/small.rs b/r7rs/src/small.rs
@@ -85,7 +85,9 @@ impl<D: Device, F: FileSystem, P: ProcessContext, C: Clock> SmallPrimitiveSet<D,
                 .map(|cons| Number::new(cons.tag() as _))
                 .unwrap_or_default()
                 .into()
-        })
+        })?;
+
+        Ok(())
     }
 }
 
@@ -111,10 +113,11 @@ impl<D: Device, F: FileSystem, P: ProcessContext, C: Clock> PrimitiveSet
                     Type::Procedure as _,
                 )?;
             }
-            Primitive::IS_RIB => memory
-                .operate_top::<Error>(|memory, value| memory.boolean(value.is_cons()).into())?,
-            Primitive::CAR => memory.operate_top::<Error>(Memory::car_value)?,
-            Primitive::CDR => memory.operate_top::<Error>(Memory::cdr_value)?,
+            Primitive::IS_RIB => {
+                memory.operate_top(|memory, value| memory.boolean(value.is_cons()).into())?
+            }
+            Primitive::CAR => memory.operate_top(Memory::car_value)?,
+            Primitive::CDR => memory.operate_top(Memory::cdr_value)?,
             Primitive::TAG => Self::tag(memory, Memory::cdr_value)?,
             Primitive::SET_CAR => Self::set_field(memory, Memory::set_car_value)?,
             Primitive::SET_CDR => Self::set_field(memory, Memory::set_cdr_value)?,

diff --git a/vm/src/memory.rs b/vm/src/memory.rs
@@ -352,11 +352,8 @@ impl<'a> Memory<'a> {
         list
     }
 
-    /// Operates a top value on a stack.
-    pub fn operate_top<E: From<Error>>(
-        &mut self,
-        operate: impl Fn(&Self, Value) -> Value,
-    ) -> Result<(), E> {
+    /// Executes an operation against a value at the top of a stack.
+    pub fn operate_top(&mut self, operate: impl Fn(&Self, Value) -> Value) -> Result<(), Error> {
         let value = self.pop();
         self.push(operate(self, value))?;
         Ok(())
@@ -380,6 +377,16 @@ impl<'a> Memory<'a> {
         Ok(())
     }
 
+    /// Executes an operation that returns `Option<Value>`.
+    pub fn operate_option(
+        &mut self,
+        mut operate: impl FnMut(&mut Memory<'a>) -> Option<Value>,
+    ) -> Result<(), Error> {
+        let value = operate(self).unwrap_or_else(|| self.boolean(false).into());
+        self.push(value)?;
+        Ok(())
+    }
+
     // Garbage collection
 
     fn collect_garbages(&mut self, cons: Option<&mut Cons>) -> Result<(), Error> {