tombl.dev
a post-component library for building user-interfaces on the web.
1import { html, type Displayable, type HTML, type Renderable } from 'dhtml'
2
3declare global {
4 var __DEV__: boolean
5}
6
7export function is_renderable(value: unknown): value is Renderable {
8 return typeof value === 'object' && value !== null && 'render' in value
9}
10
11export function is_iterable(value: unknown): value is Iterable<unknown> {
12 return typeof value === 'object' && value !== null && Symbol.iterator in value
13}
14
15export function assert(value: unknown, message?: string): asserts value {
16 if (!__DEV__) return
17 if (!value) throw new Error(message ?? 'assertion failed')
18}
19
20export const html_tag: unique symbol = Symbol()
21export function is_html(value: any): value is HTML {
22 return typeof value === 'object' && value !== null && html_tag in value
23}
24
25export function single_part_template(part: Displayable): HTML {
26 return html`${part}`
27}