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Nils Eriksson3,396 Points
We don't call printError with a parameter, how does that work ?
we dont add a parameter in request.on("error",printError); but still we can use one, how does that work ?
Also is there any good video explaining how this callback functions work ? how do i create my own? Tnx
Merritt Lawrenson13,477 Points
printError doesn't need a parameter in request.on because you define the parameter when you defined the function earlier. Like Chalkley did in the video, you can insert an anonymous callback function to print the error, but defining the callback function elsewhere makes your code modular, so you can use that callback function for, say, other errors.