typing: use Optional[T] instead of T | None for Python 3.9 compatibility #388

	name: Makefile CI

	on:
	push:
	branches:
	- 'master'
	pull_request:
	branches:
	- 'master'

	jobs:
	style:
	name: Check style
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-python@v5
	- run: pip install flake8
	- name: Style check
	run: make check-style

	rst:
	name: Check reStructuredText
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-python@v5
	- run: pip install restructuredtext_lint
	- name: reStructuredText check
	run: make check-rst

	typing:
	name: Check typing
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3
	- uses: actions/setup-python@v4
	- name: Type check
	run: \|
	. venv
	make check-typing

	examples:
	name: Check examples
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-python@v5
	- name: Examples check
	run: \|
	. venv
	make check-examples

	test:
	name: Run test suite
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-python@v5
	- name: Install dependencies (apt)
	run: sudo apt-get install -y python3-clang python3-pip
	- name: Test
	run: \|
	. venv
	make test

	docs:
	name: Check documentation
	if: github.event_name == 'pull_request'
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Install dependencies (apt)
	run: sudo apt-get install -y python3-clang python3-pip
	- name: Documentation build check
	run: \|
	. venv
	make O=-Wn html

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