Implements default constructor #24

	name: CI
	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main
	jobs:
	build:
	name: Build
	strategy:
	matrix:
	os: [ubuntu-latest]
	runs-on: ${{ matrix.os }}
	steps:
	- name: Checkout repository
	uses: actions/checkout@v4
	- name: Update Rust
	run: rustup update stable
	- name: Check code styles
	run: cargo fmt --check
	- name: Run tests
	run: cargo test
	- name: Run example
	run: \|
	import json
	import os
	from subprocess import Popen, PIPE, run
	import sys

	with Popen(["cargo", "run", "-p", "example", "--message-format", "json-render-diagnostics"], stdout=PIPE) as proc:
	for line in proc.stdout:
	line = json.loads(line)
	reason = line["reason"]
	if reason == "build-finished":
	ok = line["success"]
	break
	elif reason == "build-script-executed":
	for env in line["env"]:
	key = env[0]
	val = env[1]

	if key == "CPPBIND_METADATA":
	meta = val

	with open(os.environ["GITHUB_OUTPUT"], "a") as f:
	print(f"meta={meta}", file=f)

	if not ok:
	sys.exit(1)
	shell: python
	id: example
	- name: Upload example metadata
	uses: actions/upload-artifact@v4
	with:
	name: example-metadata-${{ runner.os }}-${{ runner.arch }}
	path: ${{ steps.example.outputs.meta }}
	if: ${{ failure() }}

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