diff options
Diffstat (limited to 'src/lib')
-rw-r--r-- | src/lib/dom.ts | 15 | ||||
-rw-r--r-- | src/lib/h.ts | 34 | ||||
-rw-r--r-- | src/lib/rx.ts | 405 |
3 files changed, 405 insertions, 49 deletions
diff --git a/src/lib/dom.ts b/src/lib/dom.ts deleted file mode 100644 index 0b6a0ab..0000000 --- a/src/lib/dom.ts +++ /dev/null @@ -1,15 +0,0 @@ -export function show(elements: Element[]): void { - document.body.innerHTML = '' - elements.forEach(element => document.body.appendChild(element)) -} - -/* Trigger animation in any case. - * - * Trigger reflow between removing and adding the classname. - * See https://css-tricks.com/restart-css-animation/ - */ -export function triggerAnimation(element: HTMLElement, animation: string) { - element.classList.remove(animation) - void element.offsetWidth - element.classList.add(animation) -} diff --git a/src/lib/h.ts b/src/lib/h.ts deleted file mode 100644 index 8b1abf3..0000000 --- a/src/lib/h.ts +++ /dev/null @@ -1,34 +0,0 @@ -type Child = Element | Text | string | number - -export default function h( - tagName: string, - attrs: object, - ...children: Child[] -): Element { - const isSvg = tagName === 'svg' || tagName === 'path' - - let elem = isSvg - ? document.createElementNS('http://www.w3.org/2000/svg', tagName) - : document.createElement(tagName) - - if (isSvg) { - Object.entries(attrs).forEach(([key, value]) => { - elem.setAttribute(key, value) - }) - } else { - elem = Object.assign(elem, attrs) - } - - for (const child of children) { - if (typeof child === 'number') - elem.append(child.toString()) - else - elem.append(child) - } - - return elem -} - -export function classNames(obj: {[key: string]: boolean }): string { - return Object.keys(obj).filter(k => obj[k]).join(' ') -} diff --git a/src/lib/rx.ts b/src/lib/rx.ts new file mode 100644 index 0000000..3f3b8d9 --- /dev/null +++ b/src/lib/rx.ts @@ -0,0 +1,405 @@ +// [1.1.0] 2023-02-13 + +// Html + +export type Html + = false + | undefined + | string + | number + | Tag + | WithVar<any> + | Array<Html> + | Rx<Html> + +interface Tag { + type: 'Tag' + tagName: string + attributes: Attributes + children?: Array<Html> + onmount?: (element: Element) => void + onunmount?: (element: Element) => void +} + +interface WithVar<A> { + type: 'WithVar' + init: A + getChildren: (v: Var<A>, update: (f: (value: A) => A) => void) => Html +} + +interface Attributes { + [key: string]: Rx<AttributeValue> | AttributeValue +} + +type AttributeValue + = undefined + | string + | number + | boolean + | ((event: Event) => void) + | ((element: Element) => void) + +function isHtml(x: any): x is Html { + return (typeof x === 'string' + || typeof x === 'number' + || isTag(x) + || isWithVar(x) + || isRx(x) + || Array.isArray(x)) +} + +type ValueOrArray<T> = T | Array<ValueOrArray<T>> + +export function h( + tagName: string, + x?: Attributes | Html, + ...children: Array<Html> +): Tag { + if (x === undefined || x === false) { + return { + type: 'Tag', + tagName, + attributes: {} + } + } else if (isHtml(x)) { + return { + type: 'Tag', + tagName, + attributes: {}, + children: [x, ...children], + } + } else { + let attributes = x as Attributes + let onmount, onunmount + if ('onmount' in attributes) { + onmount = attributes['onmount'] as (element: Element) => void + delete attributes['onmount'] + } + if ('onunmount' in attributes) { + onunmount = attributes['onunmount'] as (element: Element) => void + delete attributes['onunmount'] + } + return { + type: 'Tag', + tagName, + attributes, + children, + onmount, + onunmount + } + } +} + +export function withVar<A>(init: A, getChildren: (v: Var<A>, update: (f: (value: A) => A) => void) => Html): WithVar<A> { + return { + type: 'WithVar', + init, + getChildren + } +} + +// Rx + +export type RxAble<A> = Rx<A> | A + +export class Rx<A> { + map<B>(f: (value: A) => B): Rx<B> { + return new Map<A, B>(this, f) + } + + flatMap<B>(f: (value: A) => Rx<B>): Rx<B> { + return new FlatMap<A, B>(this, f) + } +} + +class Var<A> extends Rx<A> { + readonly type: 'Var' + readonly id: string + + constructor(id: string) { + super() + this.id = id + this.type = 'Var' + } +} + +class Map<A, B> extends Rx<B> { + readonly type: 'Map' + readonly rx: Rx<A> + readonly f: (value: A) => B + + constructor(rx: Rx<A>, f: (value: A) => B) { + super() + this.type = 'Map' + this.rx = rx + this.f = f + } +} + +class FlatMap<A, B> extends Rx<B> { + readonly type: 'FlatMap' + readonly rx: Rx<A> + readonly f: (value: A) => Rx<B> + + constructor(rx: Rx<A>, f: (value: A) => Rx<B>) { + super() + this.type = 'FlatMap' + this.rx = rx + this.f = f + } +} + +// Mount + +export function mount(html: Html): Cancelable { + const state = new State() + let appendRes = appendChild(state, document.body, html) + return appendRes.cancel +} + +interface StateEntry<A> { + value: A + subscribers: Array<(value: A) => void> +} + +class State { + readonly state: {[key: string]: StateEntry<any>} + varCounter: bigint + + constructor() { + this.state = {} + this.varCounter = BigInt(0) + } + + register<A>(initValue: A) { + const v = new Var(this.varCounter.toString()) + this.varCounter += BigInt(1) + this.state[v.id] = { + value: initValue, + subscribers: [] + } + return v + } + + unregister<A>(v: Var<A>) { + delete this.state[v.id] + } + + get<A>(v: Var<A>) { + return this.state[v.id].value + } + + update<A>(v: Var<A>, f: (value: A) => A) { + const value = f(this.state[v.id].value) + this.state[v.id].value = value + this.state[v.id].subscribers.forEach(notify => { + // Don’t notify if it has been removed from a precedent notifier + if (this.state[v.id].subscribers.indexOf(notify) !== -1) { + notify(value) + } + }) + } + + subscribe<A>(v: Var<A>, notify: (value: A) => void): Cancelable { + this.state[v.id].subscribers.push(notify) + return () => this.state[v.id].subscribers = this.state[v.id].subscribers.filter(n => n !== notify) + } +} + +// Cancelable + +type Cancelable = () => void + +const voidCancel = () => {} + +// Removable + +type Removable = () => void + +const voidRemove = () => {} + +// Rx run + +function rxRun<A>(state: State, rx: Rx<A>, effect: (value: A) => void): Cancelable { + if (isVar(rx)) { + const cancel = state.subscribe(rx, effect) + effect(state.get(rx)) + return cancel + } else if (isMap<A, any>(rx)) { + return rxRun(state, rx.rx, value => effect(rx.f(value))) + } else if (isFlatMap(rx)) { + let cancel1 = voidCancel + const cancel2 = rxRun(state, rx.rx, (value: A) => { + cancel1() + cancel1 = rxRun(state, rx.f(value), effect) + }) + return () => { + cancel2() + cancel1() + } + } else { + throw new Error(`Unrecognized rx: ${rx}`) + } +} + +function isRx<A>(x: any): x is Rx<A> { + return x !== undefined && x.type !== undefined && (x.type === "Var" || x.type === "Map" || x.type === "FlatMap") +} + +function isVar<A>(x: any): x is Var<A> { + return x.type === "Var" +} + +function isMap<A, B>(x: any): x is Map<A, B> { + return x.type === "Map" +} + +function isFlatMap<A, B>(x: any): x is FlatMap<A, B> { + return x.type === "FlatMap" +} + +// Append + +interface AppendResult { + cancel: Cancelable + remove: Removable + lastAdded?: Node +} + +function appendChild(state: State, element: Element, child: Html, lastAdded?: Node): AppendResult { + if (Array.isArray(child)) { + let cancels: Array<Cancelable> = [] + let removes: Array<Removable> = [] + child.forEach((o) => { + const appendResult = appendChild(state, element, o, lastAdded) + cancels.push(appendResult.cancel) + removes.push(appendResult.remove) + lastAdded = appendResult.lastAdded + }) + return { + cancel: () => cancels.forEach((o) => o()), + remove: () => removes.forEach((o) => o()), + lastAdded + } + } else if (typeof child == "string") { + const node = document.createTextNode(child) + appendNode(element, node, lastAdded) + return { + cancel: voidCancel, + remove: () => element.removeChild(node), + lastAdded: node + } + } else if (typeof child == "number") { + return appendChild(state, element, child.toString(), lastAdded) + } else if (isTag(child)) { + const { tagName, attributes, children, onmount, onunmount } = child + + const childElement = document.createElement(tagName) + const cancelAttributes = Object.entries(attributes).map(([key, value]) => { + if (isRx<AttributeValue>(value)) { + return rxRun(state, value, newValue => setAttribute(state, childElement, key, newValue)) + } else { + setAttribute(state, childElement, key, value) + } + }) + + const appendChildrenRes = appendChild(state, childElement, children) + + appendNode(element, childElement, lastAdded) + + if (onmount !== undefined) { + onmount(childElement) + } + + return { + cancel: () => { + cancelAttributes.forEach(cancel => cancel !== undefined ? cancel() : {}) + appendChildrenRes.cancel() + if (onunmount !== undefined) { + onunmount(childElement) + } + }, + remove: () => element.removeChild(childElement), + lastAdded: childElement, + } + } else if (isWithVar(child)) { + const { init, getChildren } = child + const v = state.register(init) + const children = getChildren(v, f => state.update(v, f)) + const appendRes = appendChild(state, element, children) + return { + cancel: () => { + appendRes.cancel() + state.unregister(v) + }, + remove: () => appendRes.remove(), + lastAdded: appendRes.lastAdded + } + } else if (isRx(child)) { + const rxBase = document.createTextNode('') + appendNode(element, rxBase, lastAdded) + let appendRes: AppendResult = { + cancel: voidCancel, + remove: voidRemove, + lastAdded: rxBase + } + const cancelRx = rxRun(state, child, (value: Html) => { + appendRes.cancel() + appendRes.remove() + appendRes = appendChild(state, element, value, rxBase) + }) + return { + cancel: () => { + appendRes.cancel() + cancelRx() + }, + remove: () => { + appendRes.remove() + element.removeChild(rxBase) + }, + lastAdded: appendRes.lastAdded, + } + } else if (child === undefined || child === false) { + return { + cancel: voidCancel, + remove: voidRemove, + lastAdded + } + } else { + throw new Error(`Unrecognized child: ${child}`) + } +} + +function isTag<A>(x: any): x is Tag { + return x !== undefined && x.type === "Tag" +} + +function isWithVar<A>(x: any): x is WithVar<A> { + return x !== undefined && x.type === "WithVar" +} + +function appendNode(base: Element, node: Node, lastAdded?: Node) { + if (lastAdded !== undefined) { + base.insertBefore(node, lastAdded.nextSibling) + } else { + base.append(node) + } +} + +function setAttribute(state: State, element: Element, key: string, attribute: AttributeValue) { + if (attribute === undefined || attribute === false) { + // Do nothing + } else if (attribute === true) { + // @ts-ignore + element[key] = "true" + } else if (typeof attribute === "number") { + // @ts-ignore + element[key] = attribute.toString() + } else if (typeof attribute === "string") { + // @ts-ignore + element[key] = attribute + } else { + // @ts-ignore + element[key] = (event: Event) => attribute(event) + } +} |