added simple example + fixed warning in ast.rs #165

	name: ci

	on: [push, pull_request]

	env:
	CARGO_TERM_COLOR: always

	jobs:
	debug:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v3
	- name: Build
	run: cargo build --verbose
	- name: Run tests
	run: cargo test --verbose

	release:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v3
	- name: Build
	run: cargo build --verbose --release
	- name: Run tests
	run: cargo test --verbose --release

	debug-nostd:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v3
	- name: Build
	run: cargo build --verbose --no-default-features --features alloc
	- name: Run tests
	run: cargo test --verbose --no-default-features --features alloc

	release-nostd:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v3
	- name: Build
	run: cargo build --verbose --release --no-default-features --features alloc
	- name: Run tests
	run: cargo test --verbose --release --no-default-features --features alloc

	c_api:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v3
	- name: Run c_api test
	run: cd c_api && ./run_test.sh

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