Optional @angular/compiler

@angular/compiler is an optional peer dependency of @cl-mcp/analyzer. React-only consumers of the pipeline never need it installed; it is required only to analyze Angular libraries or validate Angular templates.

Why it is optional

The compiler is only ever needed to parse Angular templates (for ng-content slot detection, template validation, and Storybook used-component extraction). Forcing every consumer — including React-only ones — to install it would be dead weight. So the pipeline is built to import cleanly without it and to fail loudly, with a clear message, only at the exact point a template is parsed.

How it works

There is a single place in the codebase that loads @angular/compiler: src/shared/template-parser.ts, via a guarded top-level await import(). Every other module imports compiler types only (import type), which are erased at compile time.

• All value access goes through requireAngularCompiler() — it returns the loaded module or throws AngularCompilerUnavailableError.
• isAngularCompilerAvailable() lets callers probe without throwing.

Because the load is guarded, importing @cl-mcp/analyzer — and anything that transitively imports it, including @cl-mcp/core — never throws when the package is absent. Only actually parsing an Angular template does.

Behavior when it is absent

Entry point	Behavior without @angular/compiler
Importing any package	Works — no throw at import time.
AngularFrameworkAnalyzer.analyze()	Fails fast with an install hint (AngularCompilerUnavailableError).
TemplateValidator.validate()	Returns a single angular-compiler-unavailable validation error.
React analysis & JSX validation	Unaffected.

The original load error is preserved in the message, so a version mismatch is never misreported as “not installed”.

Installing it

npm i -D @angular/compiler

Any of the supported majors work: ^17.0.0 || ^18.0.0 || ^19.0.0 || ^20.0.0.