examples.md

← Back to README | Examples | Built-ins →

---

Carv Examples

The old /examples tree was consolidated into this document and docs/samples/ so language usage is documented in one place.

Hello World + Pipes

fn double(n: int) -> int {
    return n * 2;
}

print("Hello, Carv!");
let x = 10;
x |> double |> print;  // pipe operator: works with carv run (VM) and carv build (C codegen)

String Interpolation

let name = "Carv";
let version = "0.4.0";
println(f"Welcome to {name} v{version}!");
println(f"2 + 3 = {2 + 3}");

Ownership and Borrowing

let s = "hello";
let moved = s;

fn print_len(v: &string) {
    println(len(v));
}

let msg = "world";
print_len(&msg);

Result + Match

fn divide(a: int, b: int) {
    if b == 0 {
        return Err("division by zero");
    }
    return Ok(a / b);
}

match divide(10, 2) {
    Ok(v) => println(v),
    Err(e) => println(e),
};

Modules

// math.carv
pub fn add(a: int, b: int) -> int {
    return a + b;
}

// main.carv
require { add } from "./math";
println(add(1, 2));

Native TCP Server

require "net" as net;

let listener = net.tcp_listen("127.0.0.1", 8080);
let conn = net.tcp_accept(listener);
let req = net.tcp_read(conn, 4096);
println(req);

let body = "Hello from Carv TCP server!\n";
let response =
    "HTTP/1.1 200 OK\r\n" +
    "Content-Type: text/plain\r\n" +
    "Content-Length: 28\r\n" +
    "Connection: close\r\n\r\n" +
    body;

net.tcp_write(conn, response);
net.tcp_close(conn);
net.tcp_close(listener);

Runnable Samples

All 20 sample programs in docs/samples/ work with both carv run (VM) and carv build (C codegen):

# Run with the built-in VM (no C compiler needed)
carv run docs/samples/01-hello.carv
carv run docs/samples/10-classes.carv

# Build to native binary via C
carv build docs/samples/01-hello.carv
./docs/samples/01-hello

Samples cover: basics, variables, functions, control flow, for loops, strings, compound assignment, arrays, maps, classes, methods, interfaces, impl blocks, result types, match expressions, borrowing, function composition, modules, embedded features, and advanced concepts.

---

← Back to README | Examples | Built-ins →