[R-pkg-devel] best way the handle errors conditionally

I'd like your advice on handling errors conditionally within a
function. Imagine a function that does several database operations.
The user has the option to run them inside a transaction. So the code
has somewhere near the top:

if (transaction) {
????DBI::dbBegin(conn)
}

At the end of the function there is a command which commits the
transaction.

if (transaction) {
????DBI::dbCommit(conn)
}

If something goes wrong, one reverses the database operations by
issuing the DBI::dbRollback(conn) command. The first option for
issuing that is to use tryCatch(). The drawback is that the set of
command can be a few hundred lines, which harms readability when
wrapping them into a tryCatch().

?tryCatch(
???{potentially long set of commands},
????error = function(e){
??????if (transaction) {
????????dbRollback(conn)
??????}
??????stop(e)
????}
)

Another options I've found is to set options(error = function(){}) I
assume that this has a permanent effect on the current R session? So
I should reset that as a part of the error handling?

What would be recommended: tryCatch() or options(error = ...)? Or are
there more / better solutions?