@tsrx/core
TypeScript Render Extensions (TSRX) — the shared parser and compiler
infrastructure that powers TypeScript UI frameworks.
@tsrx/core is framework-agnostic. It provides the parser, AST definitions, scope
analysis, and code-generation utilities needed to target any framework runtime
using TSRX syntax. Framework-specific packages—such as
@tsrx/react, @tsrx/solid, and the external
@tsrx/ripple—build on @tsrx/core to
produce target-runtime output.
What is TSRX?
TSRX is an extension to TypeScript's syntax — in the same spirit that JSX is an
extension to JavaScript. It adds a small set of orthogonal syntactic forms that
are ergonomic for describing reactive UI, and leaves the semantics of those forms
to the consuming framework.
A .tsrx file is a TypeScript module with TSRX enabled.
Installation
pnpm add @tsrx/core
Usage
import { analyzeTsrx, parseModule } from '@tsrx/core';
const ast = parseModule(source, 'App.tsrx');
const analysis = analyzeTsrx(ast, 'App.tsrx');
The parser produces an ESTree-compatible AST, augmented with the TSRX node types
listed below. Framework compilers walk this AST to emit their own output.
Language docs
The TSRX website is the canonical source for language documentation:
- Getting Started — install TSRX for React,
Preact, Solid, Vue, or Ripple and configure editor/AI tooling.
- Features — examples of function components,
statement templates, control flow, scoped styles, submodules, and lazy
destructuring.
- Specification — the current grammar and
parser-level semantics.
Keeping the language reference on the website avoids duplicating the specification
here and keeps package docs focused on the core parser API.
What @tsrx/core provides
parseModule(source, filename, options?) — parse a TSRX module into an
ESTree AST.
analyzeTsrx(ast, filename, options?) — run target-neutral semantic
validation before framework analysis or transformation. Pass collect: true,
typeOnly: true, or to_ts: true to collect non-fatal diagnostics for
editor/type-only output.
- Scope analysis —
createScopes, Scope, ScopeRoot, binding tracking
(import, prop, let, const, function, for_pattern, …).
- AST utilities — pattern walkers, identifier extraction, builders, location
helpers, obfuscation helpers.
- CSS support —
parseStyle, analyzeCss, renderStylesheets. CSS node
offsets are relative to the style body; a sheet parsed with a body origin
(every sheet parseModule produces) records sourceStart and a file-relative
loc, and analyzeCss anchors its :global placement diagnostics on the
selector with file-relative positions. Pass { errors, comments } to collect
them instead of throwing.
- Scoped styles —
analyzeTsrx resolves every <style> block. A standalone
block is a child of an element or fragment and is scoped to its siblings: it
styles the items beside it and everything below them, never the element that
contains it, and the compiler adds a hash class to those elements so the block's
selectors match only there. A block is an output node, so a block that is the
lone output of a @{ … } or control-flow body is
STYLE_STANDALONE_NEEDS_FRAGMENT. Raw CSS is TSRX template syntax, so a block
with CSS in it outside every @{ … }/control-flow body is
STYLE_STANDALONE_OUTSIDE_TEMPLATE; plain-TSX <style>{css}</style> is an
ordinary element. Assigned blocks (const theme = <style>…</style>) are
classified as theme (exported, applied, or $class read) or class-map, and
apply targets are resolved through real bindings, declared before use. Results
ride on each block's metadata (styleKind, styleApplies, styleApplied,
styleExported) and on program.metadata.styles, and the analysis result
exposes scopes. Target compilers use prepareStylesheetForRender(sheet, mode)
with mode: 'scope' | 'class-map' | 'theme' (a boolean still means
class-map/scope) and createStyleClassMapFromStylesheet(sheet, options),
whose object starts with $class and accepts { applied } for composed themes.
Style diagnostics use the STYLE_* and CSS_GLOBAL_PLACEMENT codes in
DIAGNOSTIC_CODES.
- HTML helpers —
isVoidElement, isBooleanAttribute, isDomProperty,
validateNesting.
- Event helpers — delegated-event utilities, event-name normalization.
- Source maps —
convertSourceMapToMappings.
See src/index.js for the full exported surface.
Non-goals
@tsrx/core does not emit runtime code. Code generation lives in framework
packages (e.g. @tsrx/ripple).
@tsrx/core does not ship a runtime. There is no reactivity, rendering, or
DOM code here.
@tsrx/core does not lock consumers to a specific output format. Multiple
compile targets can share the same parser and analysis.
License
MIT © Dominic Gannaway