error: the `Err`-variant returned from this closure is very large
   --> hugr-core/src/hugr/serialize.rs:288:71
    |
123 | /     MissingPortOffset {
124 | |         /// The node that has the port without offset.
125 | |         node: Node,
126 | |         /// The direction of the port without an offset
...   |
129 | |         op_type: OpType,
130 | |     },
    | |_____- the largest variant contains at least 157 bytes
...
288 |           let unwrap_offset = |node: Node, offset, dir, hugr: &Hugr| -> Result<usize, Self::Error> {
    |                                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^