擅长:python、mysql、java
<pre><code>def index_on(lst):
index = {val:i for i,val in enumerate(lst)}
def lookup(val):
return index.get(val, 'no')
return lookup
search = index_on(alist)
search('123-4567') # => 293 (index in alist)
search('123-4500') # => 'no' (not found)
</code></pre>