ndmitchell/hlint

bad suggestion for "redundant section"

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#1,257 opened on Jun 8, 2021

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 (1 comment) (0 reactions) (0 assignees)Haskell (1,594 stars) (208 forks)batch import
good first issue

Description

the following function has the suggestion included however following the hint results in it not compiling

weirdEq :: (Int, Int) -> (Int, Int) -> Bool
weirdEq (_, 1) (_, 1) = True
weirdEq a b = ((==) `on`) snd a b

Suggestion: Redundant section
Found:
  ((==) `on`) snd
Perhaps:
  (==) `on` snd

v3.3.1 windows and linux

Contributor guide

Tech stack
None
Domain
tooling
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Haskell experiencehlint codebase familiarity
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
40
Research direction
Investigate the 'Redundant section' rule in hlint. The false positive occurs when the section argument is itself a partial application. Examine the source code for the rule in the hlint codebase, likely in the Hint module. Check if there are existing tests for similar patterns.