iterate over an array and delete elements conditionally

The following logic:

Iterate over the URLs array and If the HTTP request with the given URL does not timeout, continue. If the URL times out, remove it from the array and continue with the next one until the array is exhausted.

Has been implemented in the following way:

@urls.delete_if do |url|
  begin
    doc = perform_request(some_params)
    break
  rescue TimeoutError
    Rails.logger.warn("URL #{url} times out, will be removed from list")
    true
  end
end

Anyone for a cleaner solution? Basically, I want to iterate over an array and remove elements from it if there is a timeout, but if the URL works loop should end and app should continue processing.

note : your break is useless, because if the block returns a falsey value, the url is kept.

Maybe it can just be a bit more expressive ?

def timeouts?( url )
  perform_request( url ) && false 
rescue TimeoutError
  true
end

@urls.delete_if {|url| timeouts?( url ) }

You could even make timeouts? a method on your @urls objects, for extra readability :

@urls.delete_if( &:timeouts? )

if you want to keep @tokland's functionnal approach, just use :

@kept_urls = @urls.reject{|url| timeouts?( url ) }

however, it would not be fully "functionnal", because timeouts may not return the same results with the same arguments, depending on the execution environment.

StackExchange Code Review Q#20151, answer score: 3