feat: add the sghi.registry module (#12)

Add the `sghi.registry` module which defines the `Registry` interface, implementing classes and helpers.

A `Registry` allows for storage and retrieval of values using unique keys. It supports basic dictionary-like operations and provides an interface for interacting with registered items.

docs/conf.py

@@ -62,6 +62,7 @@
     ("py:class", "_P"),  # type annotation only available when type checking
     ("py:class", "_RT"),  # type annotation only available when type checking
     ("py:class", "Chain[Any]"),  # Used as type annotation. Only available when type checking
+    ("py:class", "Signal"),  # Used as type annotation. Only available when type checking
     ("py:class", "TracebackType"),  # Used as type annotation. Only available when type checking
     ("py:class", "concurrent.futures._base.Executor"),  # sphinx can't find it
     ("py:class", "concurrent.futures._base.Future"),  # sphinx can't find it

docs/index.rst

@@ -45,6 +45,7 @@ API Reference
      sghi.dispatch
      sghi.disposable
      sghi.exceptions
+     sghi.registry
      sghi.task
      sghi.typing
      sghi.utils

src/sghi/app.py

@@ -19,6 +19,7 @@
 
 from .config import Config, SettingInitializer
 from .dispatch import Dispatcher
+from .registry import Registry
 
 # =============================================================================
 # GLOBAL APPLICATION/TOOL CONSTANTS
@@ -37,6 +38,20 @@
 
 """
 
+
+registry: Final[Registry] = Registry.of_proxy()
+"""The main application :class:`registry<sghi.registry.Registry>`.
+
+.. admonition:: Note: To application authors
+    :class: note
+
+    This value is set to an instance of :class:`sghi.registry.RegistryProxy`-
+    enabling the default wrapped instance to be replaced with a more
+    appropriate value during application setup.
+
+"""
+
+
 conf: Final[Config] = Config.of_proxy()
 """The application configurations.
 

src/sghi/dispatch/__init__.py

@@ -169,7 +169,7 @@ def of_proxy(
         Create a :class:`DispatcherProxy` instance that wraps the given
         ``Dispatcher`` instance.
 
-        If `source_dispatcher` is not given, it defaults to a value with
+        If ``source_dispatcher`` is not given, it defaults to a value with
         similar semantics to those returned by the :meth:`Dispatcher.of`
         factory method.
 
@@ -269,7 +269,7 @@ def __init__(self, source_dispatcher: Dispatcher) -> None:
         given source ``Dispatcher`` instance.
 
         :param source_dispatcher: The ``Dispatcher`` instance to wrap. This
-            MUST be an instance ``Dispatcher``.
+            MUST be an instance of ``Dispatcher``.
 
         :raise TypeError: If ``source_dispatcher`` is not an instance of
             ``Dispatcher``.