Add factory methods like what `@babel/types` provides

[ExE-Boss]

@babel/types provides factory methods for manually building AST trees.

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It would be helpful for webidl2 to provide a similar feature.

[saschanaz]

Sounds doable but could you provide your use case?

[ExE-Boss]

Well, @jsdom’s webidl2js currently creates IDLTypeDescriptions by using object literals: https://github.com/jsdom/webidl2js/blob/master/lib/constructs/interface.js#L327.