Remove redundant description of web-spider demo.

demos/webspider/webspider.py

@@ -1,16 +1,3 @@
-"""A trivial web-spider that crawls all the pages in http://tornadoweb.org.
-
-``spider()`` downloads the page at `base_url` and any pages it links to,
-recursively. It ignores pages that are not beneath `base_url` hierarchically.
-
-This function demonstrates `queues.Queue`, especially its methods
-`~queues.Queue.join` and `~queues.Queue.task_done`.
-The queue begins containing only
-`base_url`, and each discovered URL is added to it. We wait for
-`~queues.Queue.join` to complete before exiting. This ensures that
-the function as a whole ends when all URLs have been downloaded.
-"""
-
 # start-file
 import HTMLParser
 import time

docs/guide/queues.rst

@@ -14,12 +14,13 @@ until there is room for another item.
 A `~Queue` maintains a count of unfinished tasks, which begins at zero.
 `~Queue.put` increments the count; `~Queue.task_done` decrements it.
 
-In the web-spider example here, when a worker fetches a page it parses the
-links and puts new ones in the queue, then calls `~Queue.task_done` to
-decrement the counter once. Eventually, a worker fetches a page whose URLs have
-all been seen before, and there is also no work left in the queue. Thus that
-worker's call to `~Queue.task_done` decrements the counter to zero. The main
-coroutine, which is waiting for `~Queue.join`, is unpaused and finishes.
+In the web-spider example here, the queue begins containing only base_url. When
+a worker fetches a page it parses the links and puts new ones in the queue,
+then calls `~Queue.task_done` to decrement the counter once. Eventually, a
+worker fetches a page whose URLs have all been seen before, and there is also
+no work left in the queue. Thus that worker's call to `~Queue.task_done`
+decrements the counter to zero. The main coroutine, which is waiting for
+`~Queue.join`, is unpaused and finishes.
 
 .. literalinclude:: ../../demos/webspider/webspider.py
     :start-after: # start-file