@pyreon/core

Core component model, VNode types, lifecycle hooks, and control-flow components for Pyreon.

Install

bun add @pyreon/core

Quick Start

import { onMount, onUnmount, createContext, useContext } from "@pyreon/core"

function Counter() {
  onMount(() => {
    console.log("mounted")
  })

  return <div>Hello Pyreon</div>
}

API

VNode Creation

• h<P>(type, props, ...children): VNode -- Creates a virtual node. Accepts element tags, component functions, or Fragment.
• Fragment -- Groups children without adding a wrapper DOM element.
• EMPTY_PROPS -- Shared empty props object.

Components

• defineComponent(fn) -- Wraps a function as a named component.
• runWithHooks(instance, fn) -- Executes a function within a component's hook context.
• propagateError(error, instance) -- Propagates an error up the component tree.
• dispatchToErrorBoundary(error, instance) -- Sends an error to the nearest ErrorBoundary.

Lifecycle Hooks

• onMount(fn: () => CleanupFn | void) -- Runs after the component mounts. Optionally return a cleanup function.
• onUnmount(fn) -- Runs when the component is removed.
• onUpdate(fn) -- Runs after each reactive update.
• onErrorCaptured(fn) -- Captures errors thrown by descendant components.

Context

• createContext<T>(defaultValue?): Context<T> -- Creates a context with an optional default.
• useContext(ctx): T -- Reads the nearest provided context value.
• provide(ctx, value) -- Provides a context value for the current component's subtree (auto-cleans up on unmount).
• withContext(ctx, value, fn) -- Runs fn with the given context value.
• pushContext(map) / popContext() -- Low-level context stack manipulation.

Refs

• createRef<T>(): Ref<T> -- Creates a mutable ref object.

Control-Flow Components

• Show -- Conditionally renders children based on a when prop.
• Switch / Match -- Multi-branch conditional rendering.
• For -- Keyed list rendering with efficient reconciliation.
• Portal -- Renders children into a different DOM container.
• Suspense -- Shows fallback content while async children resolve.
• ErrorBoundary -- Catches errors in descendant components and renders a fallback.

Props Utilities

• splitProps(props, keys) -- Splits a props object into [picked, rest], preserving signal reactivity.
• mergeProps(...sources) -- Merges multiple props objects; last source wins. Preserves reactivity.
• createUniqueId(): string -- Returns an SSR-safe unique ID ("pyreon-1", "pyreon-2", etc.).

Class Utility

• cx(...values: ClassValue[]): string -- Combines class values (strings, arrays, objects, nested mix) into a single class string.

Utilities

• mapArray(source, mapFn) -- Reactively maps over an array source.
• registerErrorHandler(handler) / reportError(error, context) -- Global error telemetry.

Types

VNode, VNodeChild, VNodeChildAtom, Props, ComponentFn, ExtractProps, HigherOrderComponent, ComponentInstance, LifecycleHooks, CleanupFn, NativeItem, Ref, Context, LazyComponent, ShowProps, SwitchProps, MatchProps, ForProps, PortalProps, ErrorContext, ErrorHandler, ClassValue, TargetedEvent, PyreonHTMLAttributes, CSSProperties, StyleValue, CanvasAttributes

License

MIT