PEP 0492 -- Coroutines with async and await syntax. Issue #24017.
diff --git a/Grammar/Grammar b/Grammar/Grammar
index 6915f5f..4b193b9 100644
--- a/Grammar/Grammar
+++ b/Grammar/Grammar
@@ -21,8 +21,11 @@
decorator: '@' dotted_name [ '(' [arglist] ')' ] NEWLINE
decorators: decorator+
-decorated: decorators (classdef | funcdef)
+decorated: decorators (classdef | funcdef | async_funcdef)
+
+async_funcdef: ASYNC funcdef
funcdef: 'def' NAME parameters ['->' test] ':' suite
+
parameters: '(' [typedargslist] ')'
typedargslist: (tfpdef ['=' test] (',' tfpdef ['=' test])* [','
['*' [tfpdef] (',' tfpdef ['=' test])* [',' '**' tfpdef] | '**' tfpdef]]
@@ -65,7 +68,8 @@
nonlocal_stmt: 'nonlocal' NAME (',' NAME)*
assert_stmt: 'assert' test [',' test]
-compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | with_stmt | funcdef | classdef | decorated
+compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | with_stmt | funcdef | classdef | decorated | async_stmt
+async_stmt: ASYNC (funcdef | with_stmt | for_stmt)
if_stmt: 'if' test ':' suite ('elif' test ':' suite)* ['else' ':' suite]
while_stmt: 'while' test ':' suite ['else' ':' suite]
for_stmt: 'for' exprlist 'in' testlist ':' suite ['else' ':' suite]
@@ -99,7 +103,8 @@
arith_expr: term (('+'|'-') term)*
term: factor (('*'|'@'|'/'|'%'|'//') factor)*
factor: ('+'|'-'|'~') factor | power
-power: atom trailer* ['**' factor]
+power: atom_expr ['**' factor]
+atom_expr: [AWAIT] atom trailer*
atom: ('(' [yield_expr|testlist_comp] ')' |
'[' [testlist_comp] ']' |
'{' [dictorsetmaker] '}' |