On Wed, 2010-06-30, Kushal Kumaran wrote: > On Wed, Jun 30, 2010 at 2:04 PM, Nico Grubert <nicogrub...@yahoo.de> wrote: >> Dear list members >> >> I have this python list that represets a sitemap: >> >> tree = [{'indent': 1, 'title':'Item 1', 'hassubfolder':False}, >> {'indent': 1, 'title':'Item 2', 'hassubfolder':False}, >> {'indent': 1, 'title':'Folder 1', 'hassubfolder':True}, >> {'indent': 2, 'title':'Sub Item 1.1', 'hassubfolder':False}, >> {'indent': 2, 'title':'Sub Item 1.2', 'hassubfolder':False}, >> {'indent': 1, 'title':'Item 3', 'hassubfolder':False}, >> {'indent': 1, 'title':'Folder 2', 'hassubfolder':True}, >> {'indent': 2, 'title':'Sub Item 2.1', 'hassubfolder':False}, >> {'indent': 2, 'title':'Folder 2.1', 'hassubfolder':True}, >> {'indent': 3, 'title':'Sub Item 2.1.1', 'hassubfolder':False}, >> {'indent': 3, 'title':'Sub Item 2.1.2', 'hassubfolder':False}, >> ] >> >> From that list I want to create the following HTML code: >> >> <ul id="tree"> >> <li>Item 1</li> >> <li>Item 2</li> >> <li>Folder 1 >> <ul> >> <li>Sub Item 1.1</li> >> <li>Sub Item 1.2</li> >> </ul> >> </li> >> <li>Item 3</li> >> <li>Folder 2 >> <ul> >> <li>Sub Item 2.1</li> >> <li>Folder 2.1 >> <ul> >> <li>Sub Item 2.1.1</li> >> <li>Sub Item 2.1.2</li> >> </ul> >> </li> >> </ul> >> </li> >> </ul> >> >> If an item of the list has 'True' for the 'hassubfolder' key than a new >> "<ul><li>" must be created instead of "</li>" after its title. (See "Folder >> 2" node in the HTML code above. >> >> My problem is: How do I keep track of the closing tags while iterating over >> the python list? >> > > Use a stack? > > Whenever you start a new list, push the corresponding closing tag onto > a stack. Whenever your "indent level" decreases, pop the stack and > write out the closing tag you get. > > It's straightforward to use a python list as a stack.
Or even simpler. You keep track of your current indentation level (0, 1, ...). If level==1 and you come to an indent: 2, you generate an <ul> and increase level to 2. Similarly for going left. When you reach the end you add </ul>s to go back up to level 1 (or maybe you want to call it level 0 instead). That probably assumes you use HTML (like you say) rather than XHTML (which your example hints at). In HTML you don't need to supply the </li>s. I did all this in Perl earlier today, but in my case it was unsuitable because I skipped levels (had a list of HTML headings, wanted a table-of-contents, but sometimes a <h1> was followed by <h3> with no <h2> inbetween. I'd get invalid stuff like <ul><ul>. /Jorgen -- // Jorgen Grahn <grahn@ Oo o. . . \X/ snipabacken.se> O o . -- http://mail.python.org/mailman/listinfo/python-list