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Data & State

Statements that read and write data: set, find, db.update_user, derive, and merge.

set { }​

The primary way to write variables. Each line is target op value. See Variables and state for the full scope and operations reference.

set {
  user.balance += 10
  user.name = flow.trimmed
  user.todos << [{ title: "Buy milk", done: false }]
  user.muted toggle true
  user.profile merge { city: "NYC" }
}

The 9 operations: = (assign), += / -= (add/subtract), << / append, prepend, increment, decrement, merge, delete, toggle, ensure (set only if currently nil).

note

<< appends an array — wrap a single element: user.list << [item].

find​

Query the user database or any collection with dynamic filters. Returns matching results and a count.

let { results, count } = find(from: "users")
send.text(`There are ${count} users.`)

find supports where/match filters and a query pipeline for filtering large collections. For in-flow array filtering, the array.* builtins (array.where, array.find, array.reject) are usually simpler — see Builtins.

db.update_user​

Update a specific user's variables directly using MongoDB-style operators ($set, $inc, $push). Useful when you need to write another user's state (the current user's state is simpler with set).

db.update_user(chat_id: flow.target_uid, updates: { "$inc": { "rep": 1 } })
ParamTypeNotes
chat_idNumberThe user to update
updates!ObjectMongoDB-style update document

derive​

Compute a value via a typed transform and bind it:

let { value } = derive(expr: "input * 2", input: flow.n)

In most cases a plain set { flow.x = flow.n * 2 } is clearer; derive is for when you want an explicit transform node.

merge​

Collect multiple data inputs into a single aggregate value (commonly used to join the outputs of parallel work):

let { value } = merge(items: [flow.a, flow.b, flow.c])

See also​