[url] What does invoke mean? (#15)

Often the API section talks about invoking or matching a production without defining what that means.

E.g. "Invoke set-host on the input with url as url." but then https://specs.webplatform.org/url/webspecs/develop/#set-host only seems to take a single input argument so where is url coming from? And how does one invoke a diagram or get a return value from it? We'd need to explain that in terms of first principles.

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Reply to this email directly or view it on GitHub:
https://github.com/webspecs/url/issues/15