viewof counter = {
const Msg = folktale.adt.union.union('Msg', {
Increment() {
return {};
},
Decrement(title) {
return { title };
}
});
function update(message, model) {
if (!message) return [model, cmd.none];
return message.matchWith({
Increment: () => [model + 1, cmd.none],
Decrement: () => [model - 1, cmd.none]
});
}
function view(model, dispatch) {
const bind = events.bind(Msg, dispatch);
return h('div', {}, [
h('button', { on: { click: bind(Msg.Increment) } }, '+'),
h('div', {}, model),
h('button', { on: { click: bind(Msg.Decrement) } }, '-')
]);
}
return app({
view,
update,
init: () => 0
});
}
app = ({
view, // (model, dispatch) => vnode // call 'dispatch' with a message to trigger an update
update, // (message, model) => [model, [fn]]
init // () => model
}) => {
const container = html`<div id="tea-snabbdom-container"></div>`;
const main = (vnode, model) => {
// Render a new view
const newVnode = view(model, message => {
// Update the model upon incoming message
let newModel, commands;
[newModel, commands] = update(message, model);
// Uptate the view
main(wrapper, newModel);
// Execute side-effects
commands.forEach(f => (async () => f())());
});
// id must match the container definition
const wrapper = h('div#tea-snabbdom-container', {}, [newVnode]);
// Apply the new view
patch(vnode, wrapper);
// viewof interop: update the value
container.value = model;
// viewof interop: notify Observable of the new value
container.dispatchEvent(new CustomEvent("input", { bubbles: true }));
};
// Kick-start the main loop.
main(container, init());
// Return the container for Observable to render.
return container;
}
events = ({
// {on: {click: events.bind(Msg, dispatch)(Msg.OnClick)}}
bind(messageType, dispatch) {
return handlerOrMessage => {
if (messageType.hasInstance(handlerOrMessage)) {
return _ => dispatch(handlerOrMessage);
} else {
return e => dispatch(handlerOrMessage(e));
}
};
},
// const bind = events.bind(Msg, dispatch)
// ... {on: {input: bind(targetValue(Msg.OnInput)})}
targetValue(messageType) {
return e => {
return messageType(e.target.value);
};
}
})
debug = ({
trace: (msg, obj) => {
console.log(msg, obj);
return obj;
}
})
cmd = ({
none: []
})
One platform to build and deploy the best data apps
Experiment and prototype by building visualizations in live JavaScript notebooks. Collaborate with your team and decide which concepts to build out.
Use Observable Framework to build data apps locally. Use data loaders to build in any language or library, including Python, SQL, and R.
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