Generic connection pool class for e.g. sharing a limited number of network connections among many threads. Note: Connections are lazily created.

Example usage with block (faster):

   @pool = ConnectionPool.new { Redis.new }

   @pool.with do |redis|
     redis.lpop('my-list') if redis.llen('my-list') > 0
   end

Using optional timeout override (for that single invocation)

   @pool.with(timeout: 2.0) do |redis|
     redis.lpop('my-list') if redis.llen('my-list') > 0
   end

Example usage replacing an existing connection (slower):

   $redis = ConnectionPool.wrap { Redis.new }

   def do_work
     $redis.lpop('my-list') if $redis.llen('my-list') > 0
   end

Accepts the following options:

• :size - number of connections to pool, defaults to 5
• :timeout - amount of time to wait for a connection if none currently available, defaults to 5 seconds