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What is the corresponding TS syntax? All of these error in the TS playground 🤔

declare export default function f(): any; // "export" modifier must precede "declare" modifier

export declare default function f(): any; // lots of parsing errors

export default declare function f(): any; // expects a ; after declare

example with the syntax(playground):

export default function test(a: number): boolean;
export default function test(a: boolean): boolean;
export default function test(a: any): boolean {
    return false;
};

It looks like this.

playground

@liuxingbaoyu here is it in astexplorer (for babel parser it is to be ExportDefaultDeclaration with TSDeclareFunction in a declaration field)

Related to this.
I tested in @babel/parser 7.18.8 which produces the ExportDefaultDeclaration node.