Compiler: Class inheritance (extends) and interfaces

[PurHur]

Problem

lib/Compiler.php compileClassLike asserts null === $class->extends and empty implements. Interfaces/traits throw Unsupported class type.

Real PHP apps use simple inheritance:

class BaseController { }
class HomeController extends BaseController { }

Goal

Support single inheritance + interface stubs (vtable or dispatch table) on VM first, then JIT.

Tasks

• Remove asserts; compile extends parent name
• VM: method lookup with parent chain
• JIT: emit class metadata + method dispatch (may start with monomorphic calls only)
• PHPT: child method override + parent call
• Defer traits/multiple interfaces to follow-up

Acceptance criteria

new HomeController() calls overridden method; parent method callable via parent:: is optional stretch.

Related

• Language: Class methods and property access in JIT #58 (methods + properties in JIT)
• Reference app: examples/003-MiniWebApp (router, templates, forms) #67 (reference app may use simple controller class)