Language at a glance

The five things to know.

1. Every declaration is a kinded block

box

kind("name") {
  field = value
  child("name") {
    ...
  }
}

The kind (http, cli, package, route, …) is registered by a plugin (or the core, for package). The name in parens is the local identifier. The body is multi-line.

2. Defaults are nameless

Drop the (name) to mark a block as the project default for that kind:

box

i18n {
  locales = ["en", "zh"]
  default = "en"
}

At most one nameless block per kind in the entire project. Plugin functions like t(...) use the default.

3. Imports are always namespaced

box

import "./schema.box"               // → schema.User, schema.User[]
import "../auth/index.box"          // → auth.X        (parent dir)
import "../user-service/index.box" as users

No form pulls names into the root scope. Use export "./file.box" to re-export through a facade.

4. Translation calls are real function calls

box

description = t("cli.init.description", version = package.box.version)

t(...) is plugin-whitelisted (from @box/i18n). Other plugin functions can be registered the same way, but there's no general expression language — no if, no for, no string interpolation.

5. The file is the visibility boundary

Everything declared in a .box file is visible to importers. No per-declaration export/pub. To hide something, put it in its own file that only specific files import.

Language at a glance ​

1. Every declaration is a kinded block ​

2. Defaults are nameless ​

3. Imports are always namespaced ​

4. Translation calls are real function calls ​

5. The file is the visibility boundary ​

See also ​