Build unordered list in HTML from a python list

[Kushal Kumaran]

On Wed, Jun 30, 2010 at 2:04 PM, Nico Grubert <nicogrubert at 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.

-- 
regards,
kushal