Comments in export/import

hugr-core/src/export.rs

@@ -10,7 +10,7 @@ use crate::{
     types::{
         type_param::{TypeArgVariable, TypeParam},
         type_row::TypeRowBase,
-        CustomType, FuncTypeBase, MaybeRV, PolyFuncTypeBase, RowVariable, SumType, Type, TypeArg,
+        CustomType, FuncTypeBase, MaybeRV, PolyFuncTypeBase, RowVariable, SumType, TypeArg,
         TypeBase, TypeBound, TypeEnum, TypeRow,
     },
     Direction, Hugr, HugrView, IncomingPort, Node, Port,
@@ -1028,6 +1028,9 @@ impl<'a> Context<'a> {
     fn export_value(&mut self, value: &'a Value) -> model::TermId {
         match value {
             Value::Extension { e } => {
+                // NOTE: We have special cased arrays, integers, and floats for now.
+                // TODO: Allow arbitrary extension values to be exported as terms.
+
                 if let Some(array) = e.value().downcast_ref::<ArrayValue>() {
                     let len = self.make_term(model::Term::Nat(array.get_contents().len() as u64));
                     let element_type = self.export_type(array.get_element_type());

hugr-core/src/import.rs

@@ -1355,6 +1355,9 @@ impl<'a> Context<'a> {
                     }
                 }
 
+                // NOTE: We have special cased arrays, integers, and floats for now.
+                // TODO: Allow arbitrary extension values to be imported from terms.
+
                 if symbol_name == "collections.array.const" {
                     let element_type_term =
                         args.first().ok_or(model::ModelError::TypeError(term_id))?;
@@ -1409,7 +1412,7 @@ impl<'a> Context<'a> {
                     return Ok(ConstF64::new(value).into());
                 }
 
-                Err(error_unsupported!("constant value that is not JSON data"))
+                Err(error_unsupported!("unknown custom constant value"))
                 // TODO: This should ultimately include the following cases:
                 // - function definitions
                 // - custom constructors for values

hugr/examples/qv.rs

@@ -1,25 +1,28 @@
 #![allow(missing_docs)]
 
 use bumpalo::Bump;
-use hugr::{package::Package, std_extensions::STD_REG, Hugr, HugrView};
+use hugr::{package::Package, std_extensions::STD_REG, Hugr};
 use hugr_core::{export::export_hugr, import::import_hugr};
 use hugr_model::v0 as model;
 
 pub fn main() -> Result<(), Box<dyn std::error::Error>> {
     let bump = Bump::new();
     let hugr = load_qv();
+
     let module = export_hugr(&hugr, &bump);
+    let imported = import_hugr(&module, &STD_REG).unwrap();
+    let exported_again = export_hugr(&imported, &bump);
+
     std::fs::write(
         "qv_hugr.edn",
-        model::text::print_to_string(&module, 120).unwrap(),
+        model::text::print_to_string(&exported_again, 120).unwrap(),
     )
     .unwrap();
 
-    let binary = model::binary::write_to_vec(&module);
-    println!("size in bytes: {}", binary.len());
-    std::fs::write("qv_hugr.hugr", binary).unwrap();
+    // let binary = model::binary::write_to_vec(&module);
+    // println!("size in bytes: {}", binary.len());
+    // std::fs::write("qv_hugr.hugr", binary).unwrap();
 
-    // println!("{:#?}", module);
     Ok(())
 }