From 68f3f8b72b78583ea2c70b1872fab5d27d4fa6cb Mon Sep 17 00:00:00 2001
From: Nathaniel Starkman <nstarman@users.noreply.github.com>
Date: Wed, 17 Jul 2024 14:50:24 -0400
Subject: [PATCH] feat(space): set precedence on dispatches (#139)

Signed-off-by: nstarman <nstarman@users.noreply.github.com>
---
 conftest.py             |  2 --
 src/coordinax/_space.py | 32 ++++++++++++++++++++------------
 2 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/conftest.py b/conftest.py
index fc6f007..3a90441 100644
--- a/conftest.py
+++ b/conftest.py
@@ -1,7 +1,5 @@
 """Doctest configuration."""
 
-from __future__ import annotations
-
 from doctest import ELLIPSIS, NORMALIZE_WHITESPACE
 
 from sybil import Sybil
diff --git a/src/coordinax/_space.py b/src/coordinax/_space.py
index 7901f96..2c78b24 100644
--- a/src/coordinax/_space.py
+++ b/src/coordinax/_space.py
@@ -451,6 +451,10 @@ def to_units(
         raise NotImplementedError
 
 
+# ===============================================================
+# Related dispatches
+
+
 @dispatch  # type: ignore[misc]
 def represent_as(space: Space, target: type[AbstractVector], /) -> Space:
     """Represent the current vector to the target vector."""
@@ -459,6 +463,22 @@ def represent_as(space: Space, target: type[AbstractVector], /) -> Space:
     )
 
 
+# NOTE: need to set the precedence because `Space` is both a `Mapping` and a
+#       `dataclass`, which are both in the `replace` dispatch table.
+@dispatch(precedence=1)  # type: ignore[misc]
+def replace(obj: Space, /, **kwargs: AbstractVector) -> Space:
+    """Replace the components of the vector."""
+    return type(obj)(**{**obj, **kwargs})
+
+
+# NOTE: need to set the precedence because `Space` is both a `Mapping` and a
+#       `dataclass`, which are both in the `field_items` dispatch table.
+@dispatch(precedence=1)  # type: ignore[misc]
+def field_items(obj: Space, /) -> ItemsView[str, AbstractVector]:
+    """Return the items from a Space."""
+    return obj.items()
+
+
 # =============================================================== Temporary
 # These functions are very similar to `represent_as`, but I don't think this is
 # the best API. Until we figure out a better way to do this, we'll keep these
@@ -495,15 +515,3 @@ def temp_represent_as(
         space["speed"],
         space["length"],
     )
-
-
-@dispatch  # type: ignore[misc]
-def replace(obj: Space, /, **kwargs: AbstractVector) -> Space:
-    """Replace the components of the vector."""
-    return type(obj)(**{**obj, **kwargs})
-
-
-@dispatch  # type: ignore[misc]
-def field_items(obj: Space, /) -> ItemsView[str, AbstractVector]:
-    """Return the items from a Space."""
-    return obj.items()