From 495da292255b92dd73758fdd0e4c7d27d82b1e57 Mon Sep 17 00:00:00 2001 From: Guido van Rossum Date: Thu, 7 Mar 2019 12:38:08 -0800 Subject: bpo-35975: Support parsing earlier minor versions of Python 3 (GH-12086) This adds a `feature_version` flag to `ast.parse()` (documented) and `compile()` (hidden) that allow tweaking the parser to support older versions of the grammar. In particular if `feature_version` is 5 or 6, the hacks for the `async` and `await` keyword from PEP 492 are reinstated. (For 7 or higher, these are unconditionally treated as keywords, but they are still special tokens rather than `NAME` tokens that the parser driver recognizes.) https://bugs.python.org/issue35975 --- Lib/ast.py | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'Lib/ast.py') diff --git a/Lib/ast.py b/Lib/ast.py index 470a74b3b5..64e7a2551f 100644 --- a/Lib/ast.py +++ b/Lib/ast.py @@ -27,7 +27,8 @@ from _ast import * -def parse(source, filename='', mode='exec', *, type_comments=False): +def parse(source, filename='', mode='exec', *, + type_comments=False, feature_version=-1): """ Parse the source into an AST node. Equivalent to compile(source, filename, mode, PyCF_ONLY_AST). @@ -36,7 +37,8 @@ def parse(source, filename='', mode='exec', *, type_comments=False): flags = PyCF_ONLY_AST if type_comments: flags |= PyCF_TYPE_COMMENTS - return compile(source, filename, mode, flags) + return compile(source, filename, mode, flags, + feature_version=feature_version) def literal_eval(node_or_string): -- cgit v1.2.1