bpo-33032: Mention the implicit cache in struct.Struct() docs (GH-7700)
Mention the implicit cache in struct.Struct() docs.
Consistent with the re.compile documentation note.
diff --git a/Doc/library/struct.rst b/Doc/library/struct.rst
index d6a3cb7..bad33ac 100644
--- a/Doc/library/struct.rst
+++ b/Doc/library/struct.rst
@@ -405,6 +405,12 @@
methods is more efficient than calling the :mod:`struct` functions with the
same format since the format string only needs to be compiled once.
+ .. note::
+
+ The compiled versions of the most recent format strings passed to
+ :class:`Struct` and the module-level functions are cached, so programs
+ that use only a few format strings needn't worry about reusing a single
+ :class:`Struct` instance.
Compiled Struct objects support the following methods and attributes: