Core

Everything in TermUI sits on top of @termuijs/core. It handles the screen buffer, input decoding, layout computation, style data, events, and the application lifecycle.

If you only install one package, this is it.

Installation

·CODE

npm install @termuijs/core

What's inside

Export	What it does
App	Wires terminal, input, screen, and render loop together
Screen	Double-buffered cell grid with diff-based rendering
Renderer	Diffs screen buffers and flushes changes to stdout
Terminal	Raw mode, alt screen, cursor control, clipboard, bell, notifications, resize events
InputParser	Decodes raw stdin bytes into key, mouse, and paste events
MouseGestures	Synthesizes double-click and drag events from raw mouse events
ChordMatcher	Binds multi-key sequences (vim-style chords) to handlers
EventEmitter	Type-safe publish/subscribe
FocusManager	Tab-order focus cycling across widgets
createLayoutNode / computeLayout	Flexbox-inspired layout engine
resolveConstraints / Constraint	Constraint-based axis splitting for dashboard-style layouts
Pos / Dim / resolveLayoutVariables	Position and dimension algebra for overlay and absolute layouts
prefersReducedMotion / shouldUseColor / prefersHighContrast	Environment capability helpers
defaultStyle / mergeStyles	Style objects. colors, bold, dim, underline
parseColor	Named, hex, and RGB color parsing
stringWidth / truncate / wordWrap	Unicode-aware string measurement and wrapping

Quick example

·CODE

import { App } from '@termuijs/core'
import { Box, Text } from '@termuijs/widgets'

const root = new Box({ border: 'round', padding: 1 })
root.addChild(new Text('Hello, TermUI!', { bold: true }))

const app = new App(root)

app.events.on('key', (event) => {
    if (event.key === 'q') app.exit()
})

await app.mount()

How other packages use core

@termuijs/widgets renders into the Screen buffer and uses the layout engine for positioning
@termuijs/tss builds on top of the Style interface, adding CSS-like variables and themes
@termuijs/router plugs into the App lifecycle for screen transitions
@termuijs/motion animates style properties through the render loop

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