Capabilities of wasm?

[snnsnn]

Hi, I have a quick question. Is it possible to implement new language construct for php via wasm, say I want to write a jsx like preprocessor that can return xml like syntax from a method or function body directly in the php file.

Does wasm provides same level capability with php or zend extensions? If I understood correctly, wasm modules can be an be packaged with Composer and does not require additional step like zend extensions, which makes it perfect for distribution. Thanks.

Edit: A WebAssembly binary has no access to the PHP environment (so no access to its memory or functions). It is executed in a sandbox.