Net Library

The Net builtin library is AdeshLang's production-grade networking foundation. It provides cross-platform, zero-GC, RAII-safe networking primitives for TCP client and server streams, UDP datagram sockets, IP addressing, socket address formatting, network interface enumeration, and capability-based security policy sandboxing for SSRF defense.

All socket handles follow AdeshLang's zero-GC ownership and borrowing semantics — streams are closed deterministically upon scope exit or object drops, preventing resource leaks.

Namespace

Name	What it provides
Net	The primary networking namespace: TCP, UDP, IPAddress, SocketAddress, network interfaces, and NetworkPolicy

Importing the library

import Net;              // or import "std:Net" as Net;

Selective imports work too:

import { tcpConnect, tcpListen, udpBind, IPAddress, NetworkPolicy } from Net;

tip

All Net network operations execute non-blocking, capability-aware system calls with explicit error returns using AdeshLang's Result / Option primitives.

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TCP Networking (Net.tcpConnect & Net.tcpListen)

High-performance, buffered TCP stream connections and TCP server listeners.

Function	Description	Parameters	Returns
tcpConnect(host, port)	Connect to a remote TCP endpoint (host:port)	host: string, port: int	TcpStream
tcpListen(host, port)	Bind a TCP server listener to host:port	host: string, port: int	TcpListener

TcpStream Object Methods

• stream.read(bytesCount?): Reads bytes from the socket into a string.
• stream.write(data): Writes string or byte array payload to the socket.
• stream.close(): Explicitly closes the socket connection.
• stream.setReadTimeout(ms): Configures socket read timeout in milliseconds.
• stream.setWriteTimeout(ms): Configures socket write timeout in milliseconds.

TcpListener Object Methods

• server.accept(): Blocks until a new incoming client connects, returning a { stream: TcpStream, remoteAddr: String } connection object.
• server.close(): Shuts down the TCP listener socket.

import Net;

// 1. Start a TCP Echo Server
let server = Net.tcpListen("127.0.0.1", 8080);
print("TCP Server listening on 127.0.0.1:8080...");

// 2. Client Connection
let client = Net.tcpConnect("127.0.0.1", 8080);
client.write("PING");

// 3. Server Accept & Echo
let conn = server.accept();
let msg = conn.stream.read();
print("Server received:", msg);
conn.stream.write("PONG");

// 4. Client Read Response
let response = client.read();
print("Client received response:", response);

client.close();
server.close();

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UDP Networking (Net.udpBind)

Low-latency UDP datagram socket communication.

Function	Description	Parameters	Returns
udpBind(host, port)	Bind a UDP socket to local address host:port	host: string, port: int	UdpSocket

UdpSocket Object Methods

• socket.sendTo(data, targetHost, targetPort): Sends a datagram to targetHost:targetPort.
• socket.recvFrom(): Blocks receiving a datagram, returning { data: String, remoteHost: String, remotePort: Int }.
• socket.close(): Closes the UDP socket.

import Net;

let socket = Net.udpBind("127.0.0.1", 9090);

// Send datagram payload
socket.sendTo("Hello UDP Server", "127.0.0.1", 9090);

// Receive datagram payload
let pkt = socket.recvFrom();
print("Received UDP datagram from", pkt.remoteHost, ":", pkt.data);

socket.close();

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IP Address Representation (Net.IPAddress)

The Net.IPAddress class provides parsing, scope zone index handling, IPv4/IPv6 classification, and validation.

Function / Property	Description	Returns
Net.IPAddress.parse(ipString)	Parse IPv4 ("192.168.1.1") or IPv6 ("fe80::1%eth0") string	IPAddress
ip.version	IP version string ("v4" or "v6")	string
ip.address	Canonical string representation of the IP address	string
ip.isLoopback	True if 127.0.0.0/8 or ::1	bool
ip.isPrivate	True if RFC 1918 private network (10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) or Unique Local IPv6	bool
ip.isLinkLocal	True if 169.254.0.0/16 or fe80::/10	bool
ip.isMulticast	True if multicast destination	bool
ip.isGlobal	True if public globally routable IP address	bool

import Net;

let ip = Net.IPAddress.parse("192.168.1.50");

print("Address:", ip.address);
print("Version:", ip.version);
print("Is Private Network:", ip.isPrivate);
print("Is Loopback:", ip.isLoopback);

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Socket Address Formatting (Net.SocketAddress)

Parse formatted network socket pairs ("host:port" or "[ipv6]:port").

Function / Property	Description	Returns
Net.SocketAddress.parse(addrString)	Parse host & port formatted string	SocketAddress
addr.host	Hostname or IP string component	string
addr.port	Numeric port component	int

import Net;

let addr = Net.SocketAddress.parse("127.0.0.1:8080");
print("Host:", addr.host); // "127.0.0.1"
print("Port:", addr.port); // 8080

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Network Interfaces (Net.interfaces())

Enumerate physical and virtual network interface controllers (NICs) on the host machine.

import Net;

let nics = Net.interfaces();

for (nic in nics) {
    print("Interface:", nic.name, "| IP:", nic.ip, "| MAC:", nic.mac, "| Up:", nic.isUp);
}

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Security Policy Sandboxing (Net.NetworkPolicy())

Prevent SSRF (Server-Side Request Forgery) attacks and restrict unauthorized network access.

import Net;

let policy = Net.NetworkPolicy()
    .denyPrivateNetworks()
    .denyLoopback();

print("Policy configured:", policy);