Python NameError：未定义全局名称“NAME”
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NameError: global name 'NAME' is not defined
提问by clifgray
I have been having an interesting time building a little web scraper and I think I am doing something wrong with my variable or function scope. Whenever I try to pull out some of the functionality into separate functions it gives me the NameError: global name 'NAME' is not defined. I see that a lot of people are having a similar problem but there seems to be a lot of variation with the same error and I can't figure it out.
我在构建一个小网络抓取工具的过程中度过了一段有趣的时光，我认为我的变量或函数范围有问题。每当我尝试将某些功能提取到单独的函数中时，它都会给我 NameError: global name 'NAME' is not defined。我看到很多人都遇到了类似的问题，但似乎有很多变化与相同的错误，我无法弄清楚。
import urllib2, sys, urlparse, httplib, imageInfo
from BeautifulSoup import BeautifulSoup
from collections import deque
global visited_pages
visited_pages = []
global visit_queue
visit_queue = deque([])
global motorcycle_pages
motorcycle_pages = []
global motorcycle_pics
motorcycle_pics = []
global count
count = 0
def scrapePages(url):
#variables
max_count = 20
pic_num = 20
#decide how long it should go on...
global count
if count >= max_count:
return
#this is all of the links that have been scraped
the_links = []
soup = soupify_url(url)
#find all the links on the page
for tag in soup.findAll('a'):
the_links.append(tag.get('href'))
visited_pages.append(url)
count = count + 1
print 'number of pages visited'
print count
links_to_visit = the_links
# print 'links to visit'
# print links_to_visit
for link in links_to_visit:
if link not in visited_pages:
visit_queue.append(link)
print 'visit queue'
print visit_queue
while visit_queue:
link = visit_queue.pop()
print link
scrapePages(link)
print '***done***'
the_url = 'http://www.reddit.com/r/motorcycles'
#call the function
scrapePages(the_url)
def soupify_url(url):
try:
html = urllib2.urlopen(url).read()
except urllib2.URLError:
return
except ValueError:
return
except httplib.InvalidURL:
return
except httplib.BadStatusLine:
return
return BeautifulSoup.BeautifulSoup(html)
Here is my trackback:
这是我的引用：
Traceback (most recent call last):
File "C:\Users\clifgray\Desktop\Mis Cosas\Programming\appengine\web_scraping\src\test.py", line 68, in <module>
scrapePages(the_url)
File "C:\Users\clifgray\Desktop\Mis Cosas\Programming\appengine\web_scraping\src\test.py", line 36, in scrapePages
soup = soupify_url(url)
NameError: global name 'soupify_url' is not defined
采纳答案by Mike
Move your main code:
移动您的主要代码：
the_url = 'http://www.reddit.com/r/motorcycles'
#call the function
scrapePages(the_url)
After the point where you define soupify_url, ie. the bottom of your file.
在您定义的点之后soupify_url，即。文件的底部。
Python is reading that def scrapePages()is defined, then it tries to call it; scrapePages()wants to call a function called soupify_url()which has not yet been defined thus you're getting a:
Python 正在读取 defscrapePages()已定义，然后尝试调用它；scrapePages()想要调用一个soupify_url()尚未定义的函数，因此您将得到：
NameError: global name 'soupify_url' is not defined
Keep in mind the rule: All functions must be defined before any code that does real work
牢记规则：所有函数必须在执行实际工作的代码之前定义
If you move your main code calling scrapePages()to after the definition of soupify_url()everything will be defined and in scope, should resolve your error.
如果您将主代码调用移动scrapePages()到soupify_url()所有内容的定义都将被定义并在范围内，则应解决您的错误。
