Quick question on Otel with typescript express (converting sample to TS)

[Jhappy77]

I am new to otel and I'm using the example here as a base to get started: https://github.com/open-telemetry/opentelemetry-js-contrib/tree/main/examples/express

It's been super helpful so far, so great job to the team.

My project uses express and typescript. I have converted everything necessary to typescript successfully, except for the function filterSampler in https://github.com/open-telemetry/opentelemetry-js-contrib/blob/main/examples/express/tracer.js . In the line shouldSample(ctx, tid, spanName, spanKind, attr, links) { the TS compiler doesn't like it because none of ctx, tid, spanName, spanKind, attr or links are defined or imported anywhere in the file.

I am curious
A) are these somehow global variables? Is it expected that they aren't imported or defined in the file?
B) Do you have any recommendations to fix this?

Thanks, and cheers!