Subflows. Inputs and outputs not matching between machines

[Trying_to_learn]

(not wanting to babble on)

Ok, reading that link and sub-link to Button icons example I already am . . . confused with the flow.

In the function node:
var state = context.state || false;

I went through a horrible learning curve with context stuff.

I thought it should be:
var state = context.get("state") || false;

I shall have to let that slip as a slicker way to do it.
But just saying when I see things like that, it makes a smooth journey less smooth.