merge(3p/immer): Subtree merge at 'ad3e3556d' as 'third_party/immer'

Change-Id: I9636a41ad44b4218293833fd3e9456d9b07c731b

third_party/immer/doc/transients.rst

@@ -0,0 +1,51 @@
+.. _transient:
+
+Transients
+==========
+
+*Transients* is a concept borrowed `from Clojure
+<clojure-transients>`_, with some twists to turn make more idiomatic
+in C++.  Essentially, they are a mutable interface built on top of the
+same data structures the implements the immutable containers under the
+hood.
+
+These can be useful for :ref:`performing efficient batch
+updates<batch-update>` or :ref:`interfacing with standard
+algorithms<std-compat>`.
+
+.. _clojure-transients: https://clojure.org/reference/transients
+
+array_transient
+---------------
+
+.. doxygenclass:: immer::array_transient
+    :members:
+    :undoc-members:
+
+vector_transient
+----------------
+
+.. doxygenclass:: immer::vector_transient
+    :members:
+    :undoc-members:
+
+flex_vector_transient
+---------------------
+
+.. doxygenclass:: immer::flex_vector_transient
+    :members:
+    :undoc-members:
+
+set_transient
+-------------
+
+.. doxygenclass:: immer::set_transient
+    :members:
+    :undoc-members:
+
+map_transient
+-------------
+
+.. doxygenclass:: immer::map_transient
+    :members:
+    :undoc-members: