Status: refused by design
export const {} is not FunctionalScript. export const {} = {}; is valid JavaScript, and fjs compile refuses it by design: the demo below shows what it prints.
An exported pattern exports each name it binds, so export const {} = {}; exports nothing, and a module made of it is a module with no export (no export). JavaScript admits the text; FunctionalScript refuses it as module exports nothing.
The row mod.empty-pattern-export of refused constructs registers the refusal, and module structure gives its reason.
export const {} = {};
The demo on this page compiles sample.mjs, the module above, with this build's fjs compile, and shows the line it prints and the token it refuses. Below that it shows what JavaScript answers for the same module: undefined.
Export a name, as alternative.f.js does:
export const a = 1;
export default a;
It answers 1.
Today fjs compile prints module exports nothing at the refused token. The demo proposes what it should print instead: the reason at the same token, what JavaScript does there, and the allowed spelling, the line alternative.f.js writes, as help. The page compiles the alternative too, so the suggestion is one the compiler accepts.