The Praia Programming Language

Praia comes with an HTTP server, JSON/YAML parsing, SQLite, crypto, async/await, generators, and a pipe operator for readable data pipelines - all out of the box, no packages to install.

use "router"

let app = router.create()

app.get("/users/:id", lam{ req, params in
    let user = db.findUser(params.id)
    return http.json(user)
})

app.get("/search", lam{ req, params in
    let results = sys.read("data.json")
        |> json.parse
        |> filter(lam{ item in item.name.test(req.query) })
        |> sort
    return http.json(results)
})

app.listen(8080)

func fibonacci() {
    let a = 0
    let b = 1
    while (true) {
        yield a
        let temp = a
        a = b
        b = temp + b
    }
}

for (n in fibonacci()) {
    if (n > 1000) { break }
    print(n)
}

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Why use Praia?

Broad stdlib. HTTP client & server, JSON, YAML, SQLite, crypto, TCP/UDP, regex, and async are all built into the language. No package installs needed to start building.

Pipe operator. The |> operator turns nested calls like sort(filter(map(data, f), g)) into linear, readable chains. Data flows top-to-bottom.

Safe regex. When built with Google’s RE2 engine, every regex completes in O(n) guaranteed time. No catastrophic backtracking. Safe for user-supplied patterns in web servers.

Lightweight generators. Generators use stack snapshots - no threads, no OS resources. Create thousands of them. They integrate directly with for-in loops for lazy evaluation.

Precise numbers. 64-bit integers stay exact. 10 / 2 returns 5 (int), not 5.0. Overflow promotes to float instead of wrapping silently.

Sane defaults. Only nil and false are falsy. UPPER_CASE names warn on reassignment. for-in snapshots the collection so mutation mid-loop is safe.

Pattern matching. match supports equality, type patterns with is, and guard clauses with when.

Native C++ plugins. Load shared libraries at runtime with loadNative(). Write performance-critical code in C++, expose it to Praia as regular functions. Scaffold a plugin project with sand init --plugin.

Package manager. sand installs and manages grains (modules) from Git repositories.