getfirst and re
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From: Tim Chase on 6 Jan 2010 12:27 > I need to do something like the following: > > pat = re.compile('edit[0-9]*:[0-9]*') > check = form.getfirst(pat) > > (to check things like 'edit0:1') How do I do this? Well, you can do it either as check = pat.search(string_to_search) which is pretty plainly detailed in the help for the "re" module, both under the search() function and under the "8.2.2 Matching vs. Searching" section. Alternatively, if you plan to get the others too, you can use fi = pat.finditer(string_to_search) check = fi.next().group(0) # beware this may throw # a StopIteration if there are no more matches. which would usually be done inside a loop where the StopIteration does the Right Thing(tm). But if you're using it on HTML form text, regexps are usually the wrong tool, and you should be using an HTML parser (such as BeautifulSoup) that knows how to handle odd text and escapings better and more robustly than regexps will. -tkc
From: Tim Chase on 6 Jan 2010 12:59 Victor Subervi wrote: > On Wed, Jan 6, 2010 at 1:27 PM, Tim Chase <python.list(a)tim.thechases.com>wrote: > >> But if you're using it on HTML form text, regexps are usually the wrong >> tool, and you should be using an HTML parser (such as BeautifulSoup) that >> knows how to handle odd text and escapings better and more robustly than >> regexps will > > I have an automatically generated HTML form from which I need to extract > data to the script which this form calls (to which the information is sent). > I believe BeautifulSoup is geared to scraping pages that exist permanently > on the web. By the time BeautifulSoup was called, this page would be gone. BeautifulSoup takes string data fed to it, and builds a structure that can be neatly navigated. That string data can come from a web page, from a disk, or even a serial port, a random-character-generator, or just from HTML that's built up in memory and never sees a network or a disk. It's worth reading its documentation[1] and trying its examples to get familiar with it. -tkc [1] http://www.crummy.com/software/BeautifulSoup/documentation.html
From: Carsten Haese on 6 Jan 2010 14:09 Victor Subervi wrote: > I have an automatically generated HTML form from which I need to extract > data to the script which this form calls (to which the information is > sent). Ideally, the script that receives the submitted fields should know how the form was generated, so it knows what fields to expect. Failing that, you should realize that getfirst() is not the only way to access the contents of a cgi.FieldStorage object. If you need to know the values of all fields whose names obey a certain pattern, I recommend you start with a list of all field names in the FieldStorage object and pick out the ones whose names obey that pattern. To get the list of field names, you should consider using the .keys() method of the FieldStorage object. -Carsten
From: Carsten Haese on 8 Jan 2010 09:11 Victor Subervi wrote: > Code snippet: > [...] > > Error: > [...] > What do? After eliminating the pieces of your post that have been copied or quoted from elsewhere, I am left with a total of five words of your own to ask this question, which seems to be approximately the same amount of effort you have put into trying to figure out what's causing the error. If you put in a little bit more effort than that, you might figure out yourself what's causing the error, which should then logically lead you to how to fix the error. Good luck. -Carsten
From: Steve Holden on 8 Jan 2010 09:34
Victor Subervi wrote: > On Fri, Jan 8, 2010 at 10:11 AM, Carsten Haese <carsten.haese(a)gmail.com > <mailto:carsten.haese(a)gmail.com>> wrote: > > Victor Subervi wrote: > > Code snippet: > > [...] > > > > Error: > > [...] > > What do? > > After eliminating the pieces of your post that have been copied or > quoted from elsewhere, I am left with a total of five words of your own > to ask this question, which seems to be approximately the same amount of > effort you have put into trying to figure out what's causing the error. > > > First I get scolded for not including enough information. Now I get > scolded for including too much. Seems I can't win. I *am* putting effort > into understanding this. I'm sorry I'm not as sharp as you are in these > matters. > > params = {}, key = 'store', global cgi = <module 'cgi' from > '/usr/lib64/python2.4/cgi.pyc' >>, cgi.FieldStorage = <class cgi.FieldStorage>, ].value undefined > > TypeError: unsubscriptable object > args = ('unsubscriptable object',) > > Why is the value undefined? What is an unsubscriptable object? > TIA, > beno > What is "why"? regards Steve -- Steve Holden +1 571 484 6266 +1 800 494 3119 PyCon is coming! Atlanta, Feb 2010 http://us.pycon.org/ Holden Web LLC http://www.holdenweb.com/ UPCOMING EVENTS: http://holdenweb.eventbrite.com/ |