fp-library 0.17.0

A functional programming library for Rust featuring your favourite higher-kinded types and type classes.
Documentation
# Release Process

This document outlines the steps for releasing new versions of `fp-library` and `fp-macros`.

## Prerequisites

- Ensure the working directory is clean: `git status`.
- Ensure all verification steps pass: `just verify`.

## Release Steps

### 1. Review Changes Since Last Release

For each package being released, determine what has changed since the last release:

1.  **Find the latest tag for the package:**

    ```bash
    # For fp-library
    git tag --list 'fp-library-v*' --sort=-version:refname | head -1

    # For fp-macros
    git tag --list 'fp-macros-v*' --sort=-version:refname | head -1
    ```

2.  **Review the diff between the tag and the current state:**

    ```bash
    # View commits since the last release
    git log fp-library-vX.Y.Z..HEAD -- fp-library/

    # View the full diff for detailed inspection
    git diff fp-library-vX.Y.Z..HEAD -- fp-library/
    ```

    Replace the tag with the appropriate one for `fp-macros` when reviewing that package.

3.  **Categorize the changes** into the appropriate changelog headers:
    - **Added** - New features, new modules, new type class implementations.
    - **Changed** - Modifications to existing APIs, behavior changes, refactors that affect the public interface.
    - **Removed** - Removed features, deprecated items that have been deleted.
    - **Fixed** - Bug fixes.

    Use the commit messages (especially conventional commit prefixes like `feat:`, `fix:`, `refactor:`) as a guide, but always verify against the actual diff to ensure nothing is missed or mischaracterized.

    Record the categorized changes under the `[Unreleased]` section of `fp-library/CHANGELOG.md` and `fp-macros/CHANGELOG.md` (if applicable).

### 2. Determine Version Bump

Based on the changes identified above, follow [Semantic Versioning](https://semver.org/) with the following policy for pre-1.0.0 releases:

- **Major** (X.0.0): Reserved for when the API is declared stable.
- **Minor** (0.X.0): Incompatible API changes or significant new functionality.
- **Patch** (0.0.X): Backwards-compatible bug fixes or minor additions.

### 3. Create a Release Branch

If the features for this release are on an existing branch, use that branch directly. Otherwise, create one from `main` (ensure it's up to date first with `git checkout main && git pull`):

```bash
git checkout -b release/fp-library-vX.Y.Z
```

### 4. Finalize Changelogs

1.  Rename the `[Unreleased]` section to the new version number and date (e.g., `[0.3.0] - 2026-01-16`).
2.  Create a new empty `[Unreleased]` section at the top.

### 5. Update Versions

Search **all** files listed below for version references and update
them. Version strings may appear in multiple formats (short `"0.6"`,
long `{ version = "0.6", ... }`, prose, badges, etc.). Use grep to
find all occurrences:

```bash
grep -rn '0\.OLD_MINOR' fp-macros/Cargo.toml fp-macros/README.md \
    fp-library/Cargo.toml README.md
```

#### fp-macros (if changed)

- `fp-macros/Cargo.toml`: `version` field.
- `fp-macros/README.md`: dependency snippet in the Installation section.

#### fp-library

- `fp-library/Cargo.toml`: `version` field, and `fp-macros` dependency
  version (if fp-macros was updated).
- `README.md` (repo root): all dependency snippets (there are multiple).

### 6. Verification

Run the full suite of checks locally to catch issues before the PR:

```bash
just verify
```

This runs formatting, clippy, documentation (including the unicode check), and tests in order. Alternatively, run each step individually:

```bash
just fmt                                        # Format all files (Rust, Nix, Markdown, YAML, TOML)
just clippy --workspace --all-features          # Lint (warnings are errors)
just doc --workspace --all-features --no-deps   # Doc check (warnings are errors, rejects unicode)
just test                                       # Run tests (cached; only re-runs on source changes)
```

### 7. Commit and Open PR

1.  Stage and commit the release changes (includes `Cargo.lock`, READMEs, and any other release-related updates):

    ```bash
    git add .
    git commit -m "chore: release fp-library vX.Y.Z / fp-macros vA.B.C"
    ```

2.  Push and open a pull request:

    ```bash
    git push origin release/fp-library-vX.Y.Z
    ```

    Open a PR targeting `main`. All CI checks (tests, clippy, formatting, cargo-deny) must pass before merging. See `.github/workflows/ci.yml`.
    - **Squash and Merge** is preferred to keep the `main` branch history clean and linear.
    - **Conventional Commits** are encouraged for PR titles/squash commits (e.g., `feat:`, `fix:`, `chore:`, `refactor:`, `docs:`, etc.).

### 8. Tag and Publish

After the PR is merged, tag the release on `main`:

1.  Switch to `main` and pull the merge:

    ```bash
    git checkout main
    git pull
    ```

2.  Tag the release(s). Since crates are versioned independently, create a tag for each crate being released:

    ```bash
    # If releasing fp-library
    git tag fp-library-vX.Y.Z

    # If releasing fp-macros
    git tag fp-macros-vA.B.C
    ```

3.  Push the tag(s) to trigger the automated release workflow:

    ```bash
    git push origin --tags
    ```

The release workflow (`.github/workflows/release.yml`) will automatically:

1.  Run the full test/clippy/doc validation suite.
2.  Publish `fp-macros` to crates.io (if an `fp-macros-v*` tag was pushed).
3.  Publish `fp-library` to crates.io (if an `fp-library-v*` tag was pushed).
4.  Create a GitHub Release with auto-generated notes.

**Order matters when both crates are released together:** Push the `fp-macros` tag first and wait for its publish job to succeed before pushing the `fp-library` tag, since `fp-library` depends on `fp-macros`.

> **Note:** The release workflow requires a `CARGO_REGISTRY_TOKEN` secret configured in the repository settings.

#### Manual publishing (fallback)

If the automated workflow fails or you need to publish manually:

```bash
# Publish fp-macros first (if updated)
just cargo publish -p fp-macros
# Wait for crates.io to index it
just cargo publish -p fp-library
```

## Post-Release

- Verify the release workflow succeeded in the GitHub Actions tab.
- Verify the new version is available on [crates.io]https://crates.io/crates/fp-library.
- Verify documentation is updated on [docs.rs]https://docs.rs/fp-library.