Standard Lib

Standard system libraries. Common low(ish)-level utility functions and helpers.

import type { t } from 'jsr:@sys/std/t';
import { Num } from 'jsr:@sys/std/num';
import { Pkg } from 'jsr:@sys/std/pkg';
import { Str } from 'jsr:@sys/std/str';
import { Obj } from 'jsr:@sys/std/obj';

Runtimes

• jsr:@sys/std ← Browser + WinterTC

see also (primitives):

• jsr:@sys/types

• jsr:@sys/fs
• jsr:@sys/cli
• jsr:@sys/http
• jsr:@sys/process

• jsr:@sys/crdt
• jsr:@sys/schema

Usage

// Types:
import type * as t from 'jsr:@sys/std/t';
import type { t } from 'jsr:@sys/std';

// Common:
export { Arr } from 'jsr:@sys/std/arr';
export { Err } from 'jsr:@sys/std/error';
export { Is } from 'jsr:@sys/std/is';
export { Num } from 'jsr:@sys/std/num';
export { Pkg } from 'jsr:@sys/std/pkg';
export { Str } from 'jsr:@sys/std/str';
export { Time } from 'jsr:@sys/std/time';
export { Obj } from 'jsr:@sys/std/obj';

import { Args } from 'jsr:@sys/std/args';
import { Schedule } from 'jsr:@sys/std/async';
import { Dispose } from 'jsr:@sys/std/dispose';
import { Path } from 'jsr:@sys/std/path';
import { Signal } from 'jsr:@sys/std/signal';
import { Time } from 'jsr:@sys/std/time';
import { Rx } from 'jsr:@sys/std/rx';

// Unit-testing:
import { Testing } from 'jsr:@sys/std/testing';
import { Testing } from 'jsr:@sys/std/testing/server';

Disposal capabilities

The disposal contracts separate the authority to stop a resource from observing that resource's lifecycle:

Dispose.lifecycle() and Dispose.lifecycleAsync() create lifecycle owners. Rx.lifecycle() and Rx.lifecycleAsync() are aliases of those functions.

LifecycleView describes dispose$ and disposed; it does not change the object itself. Dispose.omitDispose() returns a separate object that keeps those properties but withholds dispose, Symbol.dispose, and Symbol.asyncDispose. This narrows the API surface; it is not a security boundary.

import type { t } from 'jsr:@sys/std/t';
import { Dispose } from 'jsr:@sys/std/dispose';

const owner = Dispose.lifecycle();
const view: t.LifecycleView = Dispose.omitDispose(owner);
const dependent = Dispose.lifecycle(view);

owner.dispose('shutdown'); // The dependent observes the stop signal; ownership never transfers.

An UntilInput may be an observable, a LifecycleView, an abort signal, or any nested combination of them. undefined is ignored. The first trigger stops the new owner; ownership of the inputs does not transfer. An already-disposed view triggers that stop on the next microtask; dispose$ remains non-replaying.