I'll raise you a polyglot script that doesn't require eval: :)<p><pre><code> 1 // len("""
console.log('javascript');
/* """)
print('python');
# */
</code></pre>
Example:<p><pre><code> # python3 /tmp/test.py
python
# node /tmp/test.js
javascript
</code></pre>
I _believe_ the only source limitations are the the JS cannot contain `"""` and Python cannot contain `*/`.