StoreSetup

It is a generic js object used to build the Store
It could be thought of as a configuration
Its declaration is:

const setup = {
    state: any|()=>any),
    getters: { [name: string]: CallStoreSetup },
    actions: { [name: string]: CallStoreSetup },
    mutators: { [name: string]: CallStoreSetup }
}

const store1 = createStore(setup)
const store2 = createStore(setup)

state

any|()=>any
Initialises the state of the STORE.
If it is a function this is executed when the STORE is created.
Then the returned value is assigned to the state of the STORE.

{
    state: () => {
        ...
        return value
    },
    ...
}

Rules

• The STATE is a JSON so there should be no complex objects (only string or number)
  and ESPECIALLY no reference to external objects!
• It is IMMUTABLE. That is, if I have a STATE it always displays the same VIEW

getters

{ [name: string]: CallStoreSetup }
A dictionary. It groups functions that allow a value to be taken from the STORE

{
    getters: {
        getValue1: (_, {state}) => state.value1,
        getValue2: (param1, {state}) => state.value2 + param1,
        ...
    },
    ...
}

Rules

• They are PURE FUNCTIONS and
  can only use the STATE and other GETTERS of the same STORE in addition, of course, to the payload
• Always return a value

actions

{ [name: string]: CallStoreSetup }
A dictionary. It groups functions which perform an atomic action. This can call external resources

Rules

• They can be async
• They can call external functions or ACTIONS from another STORE

mutators

{ [name: string]: CallStoreSetup }
A dictionary. It groups functions that change state resulting in an interface update (VIEW)

Rules

• the only functions that can replace one STATE with another STATE
  (STATEs are by themselves immutable)
• They accept a STATE and possibly a paylod and return the new modified STATE