[dounan]

The reason arrow functions and bind don't play well with PureComponents is that they return a new function instance each time. This means that the Data pure component will wastefully re-render even if none of the other props change.

[abritinthebay]

Only if you did that in the render function.

If you did this.foo = this.foo.bind(this, props.bar) in the constructor then it would be the same function each time.

[dounan]

For this specific example you don't have access to the list index in the constructor.

In general binding like that in the constructor works only if you depend on props, but at that point, there isn't a need to bind at all since you can just reference the prop in the callback.

[aidos]

If you do that in the parent constructor it only really works for a single child and then you're better off not partially evaluating and instead having it pull props.bar at execution time