Hacktoberfest 2026: the issues maintainers tagged for October, open and beginner-friendly. Browse Hacktoberfest issues

Support `LinkedList<@Refined(“x>0”) Integer>`

Open
#41 1 comment 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
java
Domain
compilers

Research direction

No source files or tests are named. Start by examining existing refinement handling and how LiquidHaskell handles list refinements, then investigate translating lists to SMT-LIB and unboxing Integer to int. Done means the LinkedList example accepts 10 and rejects -100.

Written by the indexing model from the issue text.

Description

enhancement future

Add support for refining all the items inside a List.
This is a large task with several challenges inside, some of them include:

  • supporting list refinements, see how LiquidHaskell handles them;
  • how to translate lists to SMT lib;
  • unboxing Integer to int.

Small example code:

LinkedList<@Refinement(“x>0”) Integer> li = new ArrayList<Integer>();
li.add(10); // okay
li.add(-100; // error
Dominant language
Java
Stars
67
Forks
36
Avg merge
10d 18h
Merged PRs (30d)
3

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

More from liquid-java/liquidjava

All issues in liquid-java/liquidjava

Similar issues

More Java issues

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.