interpret_leaf_op is &mut to allow impls that do caching etc.

hugr-passes/src/dataflow.rs

@@ -20,15 +20,15 @@ use hugr_core::{Hugr, Node};
 /// must implement this trait (including providing an appropriate domain type `V`).
 pub trait DFContext<V>: ConstLoader<V> {
     /// Given lattice values for each input, update lattice values for the (dataflow) outputs.
-    /// For extension ops only, excluding [MakeTuple] and [UnpackTuple].
+    /// For extension ops only, excluding [MakeTuple] and [UnpackTuple] which are handled automatically.
     /// `_outs` is an array with one element per dataflow output, each initialized to [PartialValue::Top]
     /// which is the correct value to leave if nothing can be deduced about that output.
     /// (The default does nothing, i.e. leaves `Top` for all outputs.)
     ///
     /// [MakeTuple]: hugr_core::extension::prelude::MakeTuple
     /// [UnpackTuple]: hugr_core::extension::prelude::UnpackTuple
     fn interpret_leaf_op(
-        &self,
+        &mut self,
         _node: Node,
         _e: &ExtensionOp,
         _ins: &[PartialValue<V>],

hugr-passes/src/dataflow/datalog.rs

@@ -127,7 +127,7 @@ impl<H: HugrView, V: AbstractValue> Machine<H, V> {
 }
 
 pub(super) fn run_datalog<V: AbstractValue, H: HugrView>(
-    ctx: impl DFContext<V>,
+    mut ctx: impl DFContext<V>,
     hugr: H,
     in_wire_value_proto: Vec<(Node, IncomingPort, PV<V>)>,
 ) -> AnalysisResults<V, H> {
@@ -187,7 +187,7 @@ pub(super) fn run_datalog<V: AbstractValue, H: HugrView>(
            if !op_t.is_container(),
            if let Some(sig) = op_t.dataflow_signature(),
            node_in_value_row(n, vs),
-           if let Some(outs) = propagate_leaf_op(&ctx, &hugr, *n, &vs[..], sig.output_count()),
+           if let Some(outs) = propagate_leaf_op(&mut ctx, &hugr, *n, &vs[..], sig.output_count()),
            for (p, v) in (0..).map(OutgoingPort::from).zip(outs);
 
         // DFG --------------------
@@ -329,7 +329,7 @@ pub(super) fn run_datalog<V: AbstractValue, H: HugrView>(
 }
 
 fn propagate_leaf_op<V: AbstractValue>(
-    ctx: &impl DFContext<V>,
+    ctx: &mut impl DFContext<V>,
     hugr: &impl HugrView,
     n: Node,
     ins: &[PV<V>],

hugr-passes/src/dataflow/test.rs

@@ -387,8 +387,7 @@ fn test_cfg(
     xor_and_cfg: Hugr,
 ) {
     let root = xor_and_cfg.root();
-    let results =
-        Machine::new(&xor_and_cfg).run(TestContext, [(0.into(), inp0), (1.into(), inp1)]);
+    let results = Machine::new(&xor_and_cfg).run(TestContext, [(0.into(), inp0), (1.into(), inp1)]);
 
     assert_eq!(results.read_out_wire(Wire::new(root, 0)).unwrap(), out0);
     assert_eq!(results.read_out_wire(Wire::new(root, 1)).unwrap(), out1);