ndmitchell / ndmitchell/hlint

Parse error on variable named 'pattern'

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Dominant language
Haskell
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Description

Example:

module Main where

f pattern = pattern

main = return ()

HLint v1.9.28 outputs:

 Error: Parse error: pattern
Found:
    module Main where

  > f pattern = pattern

    main = return ()


1 hint

PatternSynonyms are not enabled, so it is correct Haskell code.

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Reproduce the example with HLint v1.9.28, then trace the HLint parsing entry point for how the identifier pattern is handled when PatternSynonyms are disabled. Add a regression test using the provided module and confirm it is accepted without a parse error.

Written by the indexing model from the issue text.

Assessment

Tech stack
haskell
Domain
tooling
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
38/100

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