feat: Import model in python.

hugr-py/src/hugr/model/__init__.py

@@ -1,9 +1,10 @@
 """HUGR model data structures."""
 
-from collections.abc import Sequence
+from abc import ABC
+from collections.abc import Generator, Sequence
 from dataclasses import dataclass, field
 from enum import Enum
-from typing import Protocol
+from typing import Optional
 
 from semver import Version
 
@@ -21,7 +22,7 @@ def _current_version() -> Version:
 CURRENT_VERSION: Version = _current_version()
 
 
-class Term(Protocol):
+class Term(ABC):
     """A model term for static data such as types, constants and metadata."""
 
     def __str__(self) -> str:
@@ -33,6 +34,26 @@ def from_str(s: str) -> "Term":
         """Read the term from its string representation."""
         return rust.string_to_term(s)
 
+    def to_list_parts(self) -> Generator["SeqPart"]:
+        if isinstance(self, List):
+            for part in self.parts:
+                if isinstance(part, Splice):
+                    yield from part.seq.to_list_parts()
+                else:
+                    yield part
+        else:
+            yield Splice(self)
+
+    def to_tuple_parts(self) -> Generator["SeqPart"]:
+        if isinstance(self, Tuple):
+            for part in self.parts:
+                if isinstance(part, Splice):
+                    yield from part.seq.to_tuple_parts()
+                else:
+                    yield part
+        else:
+            yield Splice(self)
+
 
 @dataclass(frozen=True)
 class Wildcard(Term):
@@ -129,9 +150,13 @@ def from_str(s: str) -> "Symbol":
         return rust.string_to_symbol(s)
 
 
-class Op(Protocol):
+class Op(ABC):
     """The operation of a node."""
 
+    def symbol_name(self) -> str | None:
+        """Returns name of the symbol introduced by this node, if any."""
+        return None
+
 
 @dataclass(frozen=True)
 class InvalidOp(Op):
@@ -159,13 +184,19 @@ class DefineFunc(Op):
 
     symbol: Symbol
 
+    def symbol_name(self) -> str | None:
+        return self.symbol.name
+
 
 @dataclass(frozen=True)
 class DeclareFunc(Op):
     """Function declaration."""
 
     symbol: Symbol
 
+    def symbol_name(self) -> str | None:
+        return self.symbol.name
+
 
 @dataclass(frozen=True)
 class CustomOp(Op):
@@ -181,13 +212,19 @@ class DefineAlias(Op):
     symbol: Symbol
     value: Term
 
+    def symbol_name(self) -> str | None:
+        return self.symbol.name
+
 
 @dataclass(frozen=True)
 class DeclareAlias(Op):
     """Alias declaration."""
 
     symbol: Symbol
 
+    def symbol_name(self) -> str | None:
+        return self.symbol.name
+
 
 @dataclass(frozen=True)
 class TailLoop(Op):
@@ -205,20 +242,29 @@ class DeclareConstructor(Op):
 
     symbol: Symbol
 
+    def symbol_name(self) -> str | None:
+        return self.symbol.name
+
 
 @dataclass(frozen=True)
 class DeclareOperation(Op):
     """Operation declaration."""
 
     symbol: Symbol
 
+    def symbol_name(self) -> str | None:
+        return self.symbol.name
+
 
 @dataclass(frozen=True)
 class Import(Op):
     """Import operation."""
 
     name: str
 
+    def symbol_name(self) -> str | None:
+        return self.name
+
 
 @dataclass
 class Node:

hugr-py/src/hugr/model/export.py

@@ -5,8 +5,8 @@
 from typing import Generic, TypeVar, cast
 
 import hugr.model as model
-from hugr.hugr.base import Hugr, Node
-from hugr.hugr.node_port import InPort, OutPort
+from hugr.hugr.base import Hugr
+from hugr.hugr.node_port import InPort, Node, OutPort
 from hugr.ops import (
     CFG,
     DFG,