Dataview JS Link FIeld Equality Check

For example, I have the following file:

# Book A
type:: [[Book]]

Note that the Book is not yet created. It’s a “ghost” link.

Now, I want to query (JS only) files where the type is a link [[Book]]:

    .where(page => page.type === [[Book]])

The result is Book is not defined.

I tried the following where clauses with no success:

    .where(page => page.type === dv.filePath([[Book]]))
    .where(page => page.type === dv.filePath('[[Book]]'))
    .where(page => page.type === dv.filePath('Book'))
    .where(page => equal(page.type, dv.filePath('[[Book]]')))
    // etc

With DQL it’s easy as hell:

list where type = [[Book]]

But I need it as JS since it’s a part of something more complex.