Searching a file for multiple strings (PS)

Tim Chase python.list at tim.thechases.com
Sat Jan 31 21:00:27 CET 2009


>> I'm fairly new with python and am trying to build a fairly simple
>> search script.  Ultimately, I'm wanting to search a directory of files
>> for multiple user inputted keywords.  I've already written a script
>> that can search for a single string through multiple files, now I just
>> need to adapt it to multiple strings.

One more item:  if your files are large, it may be more efficient 
to scan through them incrementally rather than reading the whole 
file into memory, assuming your patterns aren't multi-line (and 
by your escaping example, I suspect they're just single-words):

   items = set(['a', 'b', 'c'])
   for fname in ['file1.txt', 'file2.txt']:
     still_to_find = items.copy()
     for line in file(fname):
       found = set()
       for item in still_to_find:
         if item in line:
           found.add(item)
       still_to_find.difference_update(found)
       if not still_to_find: break
     if still_to_find:
       print "%s: Nope" % fname
     else:
       print "%s: Yep" % fname

just one more way to do it :)

-tkc






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