deepmerge¶

Two config objects walk into a bar. One leaves with the other's nested keys.

What is it?¶

deepmerge combines objects recursively — nested properties get merged, not overwritten wholesale. Perfect for layering default settings with user overrides, or merging two partial configs without losing data three levels deep.

Access it as modules.deepmerge (it's a function, not an object with methods).

How to use¶

Pass two objects. Get one merged result:

let merged = modules.deepmerge(
  { a: 1, b: { x: 1 } },
  { b: { y: 2 }, c: 3 }
)
// { a: 1, b: { x: 1, y: 2 }, c: 3 }

Notice b.x survived while b.y was added. Shallow spread ({...a, ...b}) would have replaced b entirely.

API reference¶

Common options:

Try it¶

Merge defaults with user settings¶

Bot sends to chat. Load saved preferences from db, layer over bot defaults:

let defaults = {
  notifications: true,
  theme: { color: "blue", size: "medium" },
  language: "en"
}

let saved = db.user.get("settings") || {}
let settings = modules.deepmerge(defaults, saved)

Bot.sendMessage("Theme: " + settings.theme.color + ", size: " + settings.theme.size)

Apply a partial config update¶

params might be JSON the user sent — merge it into existing config:

let current = db.bot.get("config") || {}
let update = JSON.parse(params)

let config = modules.deepmerge(current, update)
db.bot.set("config", config)

Bot.sendMessage("Config updated.")

Notes¶

• Sync — no await needed
• Arrays are replaced by default (not concatenated). Pass a custom arrayMerge if you need different behaviour
• For simple flat objects, native spread ({...a, ...b}) may be enough — use deepmerge when nesting matters
• Official package: deepmerge on npm