Small language. Clear boundaries.

Your application.
Their scripts.
Your rules.

HollowScript is a small, statically typed language built to live inside your application. Give scripts the capabilities they need, with boundaries you control.

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1uses print
2
3fn greet(name: String): String {
4    return "Hello, ${name}"
5}
6
7constant message = greet("HollowScript")
8
9effect print(message)

Example output

Hello, HollowScript

A real program, illustrated. Run your first .hws file

Built to embedStatically typedCapability basedA closer look

Built for the host application

Small and embeddable

No garbage-collector tuning, no ambient authority. A language designed to live inside a host application, with a specification you can read end to end.

Clarity before execution

Every expression has a type known before the program runs. Optionals, records, enums, generics and Result make the shape of your program explicit.

You set the boundaries

A script can only print, open a file or reach the network when the host grants the capability and the script declares it with uses.

A language you can read

uses print

record Task = { title: String, priority: Int, done: Bool }

fn describe(t: Task): String {
    if t.done {
        return "${t.title}: done"
    }
    return "${t.title}: priority ${t.priority}"
}

constant tasks: [Task] = [
    { title: "Write the parser", priority: 1, done: false },
    { title: "Freeze the spec", priority: 1, done: true }
]

for t in tasks {
    effect print(describe(t))
}

Output:

Write the parser: priority 1
Freeze the spec: done

Explore HollowScript

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Read the specificationThe complete language, standard library and diagnostic reference.