I'm accessing web pages by looping over a couple of variables to insert into the URL
There will be occasional 404 errors.
How do I insert some sort of catch for these pages to avoid breaking the code. I currently use the XML package but of course could load others if appropriate
Most of times I use
RCurl::url.exists(). In case you have a list or a data frame containing all the urls you can try this:
map(p, ~ifelse(RCurl::url.exists(.), ., NA))