Question

What type of language convention has the author used to separate the declarative sentence from the disruptive phrase in this excerpt from "Totally like whatever, you know?"

"Declarative sentences—so--called
because they used to, like, DECLARE things to be true, okay,
as opposed to other things are, like, totally, you know, not—
have been infected by a totally hip
and tragically cool interrogative tone?"

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