sys (System)

The sys module provides access to system-level features. All functions require --allow sys at runtime.

Import

import { random, randomRange, env, args, sleep } from sys;

Functions

random

Returns a random positive integer.

import { random } from sys;

int main() {
    int r = random();
    print(r);     // e.g. 1634872934
    return 0;
}

The result comes from a general-purpose CSPRNG. For cryptographic randomness use the planned crypto module.

randomRange

Returns a random integer between min (inclusive) and max (exclusive).

import { randomRange } from sys;

int main() {
    int dice = randomRange(1, 7);   // 1 to 6
    print(dice);
    return 0;
}

env

Returns the value of an environment variable, or an empty string if not set.

import { env } from sys;

int main() {
    string home = env("HOME");
    print(home);     // e.g. "/home/saqut"
    return 0;
}

args

Returns the command-line arguments passed to the program as a string array.

import { args } from sys;

int main() {
    string[] a = args();
    for (int i = 0; i < a.length; i = i + 1) {
        print(a[i]);
    }
    return 0;
}

The first element (a[0]) is the program name; following elements are the arguments.

saqut run --allow sys prog.sqt hello world
# a[0] = "prog.sqt"
# a[1] = "hello"
# a[2] = "world"

sleep

Pauses the program for the given number of seconds (supports fractional).

import { sleep } from sys;

int main() {
    print("waiting...");
    sleep(1.5);
    print("done");
    return 0;
}

Run with sys access

saqut run --allow sys program.sqt