[Python-Dev] What does a double coding cookie mean? (original) (raw)

Brett Cannon brett at python.org
Tue Mar 15 17:04:57 EDT 2016

On Tue, 15 Mar 2016 at 13:31 Guido van Rossum <guido at python.org> wrote:

I came across a file that had two different coding cookies -- one on the first line and one on the second. CPython uses the first, but mypy happens to use the second. I couldn't find anything in the spec or docs ruling out the second interpretation. Does anyone have a suggestion (apart from following CPython)?

Reference: https://github.com/python/mypy/issues/1281

I think the spirit of PEP 263 is for the first specified encoding to win as the support of two lines is to support shebangs and not multiple encodings :) . I also think the fact that tokenize.detectencoding() <https://docs.python.org/3/library/tokenize.html#tokenize.detect_encoding> doesn't automatically read two lines from its input also suggests the intent is "first encoding wins" (and that is the semantics of the function). -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.python.org/pipermail/python-dev/attachments/20160315/a433936a/attachment.html>

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