check if react component is mounted using recompose

ContainerMyComponent.js

import { compose, lifecycle, mapProps, withState } from 'recompose';
import MyComponent from '../components/MyComponent';

let isMounted = false;

const enhance = compose(
  lifecycle({
    componentDidMount() {
      isMounted = true;
    },
    componentWillUnmount() {
      isMounted = false;
    },
  }),
  withState('error', 'setError', ''),
  mapProps(({
    setError,
    ...state,
  }) => ({
    onSubmit: (e) => {
      e.preventDefault();

      // Remote method goes here...
      HTTP.get('/', (err, res) => {
        if (isMounted && error) setError(err);
      });
    },
    ...state,
  })),
);

export default enhance(MyComponent);

How about several instances of the same component?
I suppose, all instances will use the same variable.