> FP doesn't demand the parameters stay the same. It also allows for outputs of a function to get put back in as a parameter in a subsequent invocation, which is what happens to the context.
My point is that _you as the caller_ are _not_ doing this when calling a stateful component Foo. Foo mutates between events and state is entirely encapsulated, so you are getting different results from the same question. The caller doesn't care about the internal execution model of Foo and React. A functional interface is _only_ satisfied if the function is referentially transparent. Which in this case it is not.
If all you can do is send messages and observe behavior from outside. It behaves exactly like an Object and not like a Function from the perspective of the caller.
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You are arguing in terms of the implementer of a stateful component. You are thinking in terms of how React/useState behaves from inside your component and further up the call stack. And in this context I agree. You can think of useState as part of your signature so to speak. In fact the hooks rules prevent you from doing things that violate this mental model.
But that's not what I'm talking about. I'm talking about the practical, real world perspective of a caller and whether they observe functional or object oriented behavior from your component.
My point is that _you as the caller_ are _not_ doing this when calling a stateful component Foo. Foo mutates between events and state is entirely encapsulated, so you are getting different results from the same question. The caller doesn't care about the internal execution model of Foo and React. A functional interface is _only_ satisfied if the function is referentially transparent. Which in this case it is not.
If all you can do is send messages and observe behavior from outside. It behaves exactly like an Object and not like a Function from the perspective of the caller.
---
You are arguing in terms of the implementer of a stateful component. You are thinking in terms of how React/useState behaves from inside your component and further up the call stack. And in this context I agree. You can think of useState as part of your signature so to speak. In fact the hooks rules prevent you from doing things that violate this mental model.
But that's not what I'm talking about. I'm talking about the practical, real world perspective of a caller and whether they observe functional or object oriented behavior from your component.