Make enumerateAsDict() Accept a Throwing Function

[philipbel]

Parser.enumerateAsArray() catches errors and throws CSVParseError.generic error indicated the row on which the block threw.

As far as I can tell, there should be no impact on existing code that passes a non-throwing function to enumerateAsDict().

• Tests pass.

[DivineDominion]

The idea makes perfect sense, thanks for the PR. And sorry for the delay, this went under my radar!

I left 2 change requests at the relevant code sections.

But I couldn't leave a PR comment on unchanges lines, so: could you also rephrase the - Throws: docstring to add that it may forward the rowCallback error, if any, to all functions that depend on this? (You essentially found and touched all relevant parts in your PR already I believe)

Thanks!

[DivineDominion]

You're right, this doesn't change usage because the function is throwing anyway.

But could you avoid catching, wrapping, and rethrowing the error? User code throwing a MyVerySpecificError on failure in this callback will likely want to work with and maybe even catch MyVerySpecificError, not CSVParseError.generic, losing the original error's information completely here.

For context: I'm also not a fan of wrapping-and-rethrowing, because that adds another step to the debugging flow when you need to inspect the stack.

Just let rowCallback's error propagate will do The Right Thing in more cases 👍

[DivineDominion]

Same as above here, please:

Suggested change

	do {
	try rowCallback(fields)
	} catch {
	throw CSVParseError.generic(message: "Error thrown by block for row \(rowIndex)")
	}
	try rowCallback(fields)