Reactive counter, in Lua on WASM

local h = require("h").h
local reactive = require("reactive")

local count, setCount = reactive.signal(0)

local root = h("div", { class = "flex flex-col gap-4 items-start" },
    h("div", { class = "label text-accent" }, "Counter · one Lua signal"),
    h("p", { class = "text-[38px] font-sans font-semibold text-ink tracking-[-.03em] leading-none" }, function()
        return "count = " .. count()
    end),
    h("div", { class = "flex flex-row gap-2 pt-2" },
        h("button", {
            class = "btn btn-sm btn-outline",
            onClick = function() setCount(count() - 1) end,
        }, "decrement"),
        h("button", {
            class = "btn btn-sm btn-ink",
            onClick = function() setCount(count() + 1) end,
        }, "increment"),
        h("button", {
            class = "btn btn-sm btn-ghost",
            onClick = function() setCount(0) end,
        }, "reset")
    ),
    h("div", { class = "mono-sm pt-4 border-t border-rule w-full" }, function()
        return "signal updated " .. count() .. " time(s) this session"
    end)
)

dom.mount(root, "#app")

The exact module running on the left. One signal, three handlers; each text closure re-runs whenever count changes, with no virtual DOM diff.

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