feat: fill out array ops (#1491)

Closes #1320

---------

Co-authored-by: Agustín Borgna <121866228+aborgna-q@users.noreply.github.com>

hugr-core/src/extension/prelude.rs

@@ -11,7 +11,8 @@ use crate::extension::{
     ConstFold, ExtensionId, ExtensionSet, OpDef, SignatureError, SignatureFunc, TypeDefBound,
 };
 use crate::ops::constant::{CustomCheckFailure, CustomConst, ValueName};
-use crate::ops::{ExtensionOp, NamedOp, OpName, Value};
+use crate::ops::OpName;
+use crate::ops::{NamedOp, Value};
 use crate::types::type_param::{TypeArg, TypeParam};
 use crate::types::{
     CustomType, FuncValueType, PolyFuncType, PolyFuncTypeRV, Signature, SumType, Type, TypeBound,
@@ -22,30 +23,11 @@ use crate::{type_row, Extension};
 
 use strum_macros::{EnumIter, EnumString, IntoStaticStr};
 
-use super::{ExtensionRegistry, SignatureFromArgs};
-struct ArrayOpCustom;
+use super::ExtensionRegistry;
 
-const MAX: &[TypeParam; 1] = &[TypeParam::max_nat()];
-impl SignatureFromArgs for ArrayOpCustom {
-    fn compute_signature(&self, arg_values: &[TypeArg]) -> Result<PolyFuncTypeRV, SignatureError> {
-        let [TypeArg::BoundedNat { n }] = *arg_values else {
-            return Err(SignatureError::InvalidTypeArgs);
-        };
-        let elem_ty_var = Type::new_var_use(0, TypeBound::Any);
-
-        let var_arg_row = vec![elem_ty_var.clone(); n as usize];
-        let other_row = vec![array_type(TypeArg::BoundedNat { n }, elem_ty_var.clone())];
-
-        Ok(PolyFuncTypeRV::new(
-            vec![TypeBound::Any.into()],
-            FuncValueType::new(var_arg_row, other_row),
-        ))
-    }
-
-    fn static_params(&self) -> &[TypeParam] {
-        MAX
-    }
-}
+/// Array type and operations.
+pub mod array;
+pub use array::{array_type, new_array_op, ArrayOp, ArrayOpDef, ARRAY_TYPE_NAME, NEW_ARRAY_OP_ID};
 
 /// Name of prelude extension.
 pub const PRELUDE_ID: ExtensionId = ExtensionId::new_unchecked("prelude");
@@ -76,19 +58,12 @@ lazy_static! {
             )
             .unwrap();
         prelude.add_type(
-                TypeName::new_inline("array"),
+                TypeName::new_inline(ARRAY_TYPE_NAME),
                 vec![ TypeParam::max_nat(), TypeBound::Any.into()],
                 "array".into(),
                 TypeDefBound::from_params(vec![1] ),
             )
             .unwrap();
-        prelude
-            .add_op(
-                NEW_ARRAY_OP_ID,
-                "Create a new array from elements".to_string(),
-                ArrayOpCustom,
-            )
-            .unwrap();
 
         prelude
             .add_type(
@@ -125,6 +100,7 @@ lazy_static! {
         TupleOpDef::load_all_ops(&mut prelude).unwrap();
         NoopDef.add_to_extension(&mut prelude).unwrap();
         LiftDef.add_to_extension(&mut prelude).unwrap();
+        array::ArrayOpDef::load_all_ops(&mut prelude).unwrap();
         prelude
     };
     /// An extension registry containing only the prelude
@@ -152,18 +128,6 @@ pub const USIZE_T: Type = Type::new_extension(USIZE_CUSTOM_T);
 /// Boolean type - Sum of two units.
 pub const BOOL_T: Type = Type::new_unit_sum(2);
 
-/// Initialize a new array of element type `element_ty` of length `size`
-pub fn array_type(size: impl Into<TypeArg>, element_ty: Type) -> Type {
-    let array_def = PRELUDE.get_type("array").unwrap();
-    let custom_t = array_def
-        .instantiate(vec![size.into(), element_ty.into()])
-        .unwrap();
-    Type::new_extension(custom_t)
-}
-
-/// Name of the operation in the prelude for creating new arrays.
-pub const NEW_ARRAY_OP_ID: OpName = OpName::new_inline("new_array");
-
 /// Name of the prelude panic operation.
 ///
 /// This operation can have any input and any output wires; it is instantiated
@@ -175,20 +139,6 @@ pub const NEW_ARRAY_OP_ID: OpName = OpName::new_inline("new_array");
 /// satisfied.
 pub const PANIC_OP_ID: OpName = OpName::new_inline("panic");
 
-/// Initialize a new array op of element type `element_ty` of length `size`
-pub fn new_array_op(element_ty: Type, size: u64) -> ExtensionOp {
-    PRELUDE
-        .instantiate_extension_op(
-            &NEW_ARRAY_OP_ID,
-            vec![
-                TypeArg::BoundedNat { n: size },
-                TypeArg::Type { ty: element_ty },
-            ],
-            &PRELUDE_REGISTRY,
-        )
-        .unwrap()
-}
-
 /// Name of the string type.
 pub const STRING_TYPE_NAME: TypeName = TypeName::new_inline("string");
 
@@ -934,10 +884,11 @@ impl MakeRegisteredOp for Lift {
 
 #[cfg(test)]
 mod test {
+    use crate::builder::inout_sig;
     use crate::std_extensions::arithmetic::float_ops::FLOAT_OPS_REGISTRY;
     use crate::std_extensions::arithmetic::float_types::{ConstF64, FLOAT64_TYPE};
     use crate::{
-        builder::{endo_sig, inout_sig, DFGBuilder, Dataflow, DataflowHugr},
+        builder::{endo_sig, DFGBuilder, Dataflow, DataflowHugr},
         utils::test_quantum_extension::cx_gate,
         Hugr, Wire,
     };