import { type Previous } from "https://deno.land/x/dendron_exports@v0.2.2/deps/micromark.ts";
Guard whether code
can come before the construct.
In certain cases a construct can hook into many potential start characters. Instead of setting up an attempt to parse that construct for most characters, this is a speedy way to reduce that.
definition: (this: TokenizeContext, code: Code) => boolean