@solid-primitives/composites

Composable reactive primitives, extending the createEffect, createComputed, createMemo behaviors using composable and reusable modifiers.

List of officially available modifiers

Installation

npm install @solid-primitives/composites
# or
yarn add @solid-primitives/composites

How to use it

createCompositeEffect

When used alone, it works as createEffect(on()). But it can be combined with a set of Modifiers extending it's functionality.

const [counter, setCounter] = createSignal(0);

// alone:
createCompositeEffect(counter, n => console.log(n));

// accepts "defer" option, same as on()
createCompositeEffect(counter, n => console.log(n), { defer: true });

// with filter:
createCompositeEffect(debounced(counter, n => console.log(n), { wait: 300 }));

// with nested filters:
const { stop, pause } = createCompositeEffect(stoppable(pausable(counter, n => console.log(n))));

createCompositeComputed

Similar to createCompositeEffect, but it uses createComputed instead.

The usage is the same as createCompositeEffect

const { ignoring } = createCompositeComputed(
  ignorable(counter, n => console.log(n)),
  { defer: true }
);

createCompositeMemo

Apply the same modifiers to createMemo. Works simmilary to the ones above, but there are some differences:

• The returned value will be: Accessor if you don't use modifiers, or [Accessor, ModifierReturns] if you do.
• Accepts additional equals in options - a custom comparison function

const double = createCompositeMemo(counter, n => n * 2, { value: 0 });

// if you don't set the "value" option, the memo might return undefined
const [double, { pause, resume }] = createCompositeMemo(
  pausable(counter, n => n * 2),
  { value: 0 }
);

createCompositeRenderEffect

A createCompositeEffect that runs during the render phase as DOM elements are created and updated but not necessarily connected.

const { ignore } = createCompositeRenderEffect(stoppable(ignorable(counter, n => n * 2)));

Available Modifiers

import {
  stoppable,
  once,
  atMost,
  debounce,
  throttle,
  whenever,
  pausable,
  ignorable
} from "@solid-primitives/composites";

stoppable

returns { stop: StopEffect }, that can be used to manually dispose of the effects.

const { stop } = createCompositeEffect(stoppable(counter, n => console.log(n)));

once

disposes itself on the first captured change. Set the defer option to true, otherwise the callback will run and dispose itself on the initial setup.

createCompositeEffect(
  once(counter, n => console.log(n)),
  { defer: true }
);

atMost

you specify the number of times it can triggered, until disposes itself.

const { count } = createCompositeEffect(atMost(counter, n => console.log(n), { limit: 8 }));

debounce

debounces callback

const position = createScrollObserver();

createCompositeEffect(debounce(position, x => console.log(x), 300));

throttle

The callback is throttled

const position = createScrollObserver();

createCompositeEffect(throttle(position, x => console.log(x), 300));

whenever

Runs callback each time the source is truthy.

setInterval(() => setCount(p => p + 1), 1000);

createCompositeEffect(
  whenever(
    () => count() > 5,
    () => console.log(count())
  )
);
// will fire on each count change, if count is gt 5
// => 6, 7, 8, 9, 10, ...

createCompositeEffect(
  whenever(
    createMemo(() => count() > 5),
    () => console.log(count())
  )
);
// will fire only when the memo changes
// => 6

pausable

Manually controll if the callback gets to be executed

const { pause, resume, toggle } = createCompositeEffect(
  pausable(counter, x => console.log(x), { active: false })
);

ignorable

Somewhat similar to pausable, but ignore changes that would cause the next effect to run.

Preferably use this with createCompositComputed. As for createCompositEffect: since Solid batches together changes made in effects, the usage inside and outside effects will differ.

const { ignoreNext, ignore } = createCompositComputed(ignorable(
   counter,
   x => {
      // next effect will be ignored:
      ignoreNext()
      setCounter(p => p + 1)

      // is using createCompositEffect, this also will be ignored
      // but in createCompositComputed it won't be
      setCounter(5)
   }
));


const ignoreMe = () => {
   ignore(() => {
      // both changes will be ignored:
      setCounter(420)
      setCounter(69)
   })
   // but not this one:
   setCounter(p => p + 2)
}

// this watcher will work normally,
// ignoring only affects the one above
createCompositeEffect(counter, () => {...})

createModifier

A utility for creating your own modifiers. Each available modifier has been made using it. It accepts two arguments:

1. A callback modifier — function that is executed when your modifier gets attached to the createComposite___. Here you get to modify the effect callback by attatching your logic to it.

2. A boolean, that if true requires the usage of inner createRoot to provide a stop() function for disposing of the effect permanently.

// types:
function createModifier<Config, Returns, RequireStop>(
  cb_modifier: (
    source: Fn<any> | Fn<any>[], // like source of "on"
    callback: EffectCallback, // like callback of "on"
    config: Config, // config for your modifier
    stop: StopEffect | undefined // a StopEffect if RequireStop
  ) => [CustomCallback, Returns], // return your modified callback and custom return values
  requireStop?: RequireStop // true if you want to use StopEffect
): Modifier {}

// modifier that doesn't use "stop()"
const yourModifier = createModifier<{ myOption: boolean }, { value: string }>(
  (source, callback, config) => {
    const modifiedCallback = (...a) => {
      // is's important to run the previous callback here (modified callback of previous modifier)
      // also to be compatable with `createCompositeMemo` this should return a value
      return callback(...a);
    };
    return [modifiedCallback, { value: "this will get returned" }];
  }
);

// modifier that does require "stop()"
// notice the double "true" to use stop()
const yourModifier = createModifier<void, { value: string }, true>(
  (source, callback, config, stop) => {
    const modifiedCallback = (...a) => {
      /* here you can use stop() */
      return callback(...a);
    };

    return [modifiedCallback, { value: "this will get returned" }];
  },
  true
);

See the implementations of official modifiers for better reference.

Changelog

Expand Changelog

1.0.0

Initial realease

1.0.4

Adjusted documentation and published CJS support.

1.0.5

Updated to Solid 1.3

1.0.6

Minor improvements

Acknowledgements

Designed and developed by thetarnav based on:

• VueUse
• solid-rx