Parenthesize lambdas on left side of operators#135
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mdgriffith merged 1 commit intoApr 21, 2026
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When a lambda appeared as the left operand of <| (pipeLeft), it was
rendered without parentheses:
\x -> x <| "hello"
This is parsed as \x -> (x <| "hello"), not (\x -> x) <| "hello".
The fix extends the existing right-side lambda parenthesization
(from PR mdgriffith#132) to also handle the left side.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
miniBill
approved these changes
Apr 6, 2026
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When a lambda appeared as the left operand of
<|, it was rendered without parentheses:Which is semantically different, it incorrectly results in this precedence when Elm parses it
\x -> (x <| "hello").The fix extends the existing right-side lambda parenthesization from #132 to also handle the left side.