Cannot parse the unit value in refinement bounds

Description

{-@
    testee :: forall <
                p :: Int -> () -> Int -> Bool
              , q :: Int -> () -> Int -> Bool
              >.
              { n :: Int |- Int<p n ()> <: Int<q n ()> }
              Int
@-}
testee :: Int
testee = 42

{-@
    testee :: forall <
                p :: Int -> Int -> Int -> Bool
              , q :: Int -> Int -> Int -> Bool
              >.
              { n :: Int |- Int<p n 42> <: Int<q n 42> }
              Int
@-}
testee :: Int
testee = 42

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

Haskellliquid typesparsing

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

20

Research direction

Investigate the parser for refinement bounds in liquidhaskell. The issue shows that unit literal `()` fails while other literals like `42` work. Look at the code that handles parsing of literals in refinement type expressions, and identify where unit literals are not handled. Check if there is a specific parse rule for unit that might be missing.