bpo-39868: Update Language Reference for PEP 572. (GH-18793)
(cherry picked from commit 8bae21962bab2fac7630982abd73676b89930902)
Co-authored-by: Brandt Bucher <brandtbucher@gmail.com>
diff --git a/Doc/reference/expressions.rst b/Doc/reference/expressions.rst
index d9db33a..3fcc5e1 100644
--- a/Doc/reference/expressions.rst
+++ b/Doc/reference/expressions.rst
@@ -178,7 +178,7 @@
Common syntax elements for comprehensions are:
.. productionlist::
- comprehension: `expression` `comp_for`
+ comprehension: `assignment_expression` `comp_for`
comp_for: ["async"] "for" `target_list` "in" `or_test` [`comp_iter`]
comp_iter: `comp_for` | `comp_if`
comp_if: "if" `expression_nocond` [`comp_iter`]
@@ -911,7 +911,8 @@
: ["," `keywords_arguments`]
: | `starred_and_keywords` ["," `keywords_arguments`]
: | `keywords_arguments`
- positional_arguments: ["*"] `expression` ("," ["*"] `expression`)*
+ positional_arguments: positional_item ("," positional_item)*
+ positional_item: `assignment_expression` | "*" `expression`
starred_and_keywords: ("*" `expression` | `keyword_item`)
: ("," "*" `expression` | "," `keyword_item`)*
keywords_arguments: (`keyword_item` | "**" `expression`)
@@ -1642,6 +1643,17 @@
(for example, ``not 'foo'`` produces ``False`` rather than ``''``.)
+Assignment expressions
+======================
+
+.. productionlist::
+ assignment_expression: [`identifier` ":="] `expression`
+
+.. TODO: BPO-39868
+
+See :pep:`572` for more details about assignment expressions.
+
+
.. _if_expr:
Conditional expressions
@@ -1711,7 +1723,7 @@
expression_list: `expression` ("," `expression`)* [","]
starred_list: `starred_item` ("," `starred_item`)* [","]
starred_expression: `expression` | (`starred_item` ",")* [`starred_item`]
- starred_item: `expression` | "*" `or_expr`
+ starred_item: `assignment_expression` | "*" `or_expr`
.. index:: object: tuple