[Zope3-Users] Re: [Z3lab-checkins] r24502 - in z3lab/cpsskins/trunk: . browser/editor browser/skin elements/formats

[Florent Guillaume]

On 28 Jun 2005, at 23:39, svn at nuxeo.com wrote:
> Author: jmorliaguet
> Date: Tue Jun 28 23:39:48 2005
> New Revision: 24502
>
> Modified: z3lab/cpsskins/trunk/elements/formats/boxlayout.py
> ====================================================================== 
> ========
> --- z3lab/cpsskins/trunk/elements/formats/boxlayout.py    (original)
> +++ z3lab/cpsskins/trunk/elements/formats/boxlayout.py    Tue Jun  
> 28 23:39:48 2005
> @@ -89,43 +89,54 @@
>          else:
>              self.markup = ''
>
> +################################################################
> +
> +def renderItems(content, start='', repeat='%s', separator='',  
> end='', **kw):
> +    if IMenuItems.providedBy(content):
> +        items_markup = [start]
> +        items_append = items_markup.append
> +        for item in content:
> +            items_append(repeat % (item['url'], item['title']))
> +            items_append(separator)
> +        items_append(end)
> +        return ''.join(items_markup)
> +    else:
> +        return ''

In general in Zope 3 it's my understanding that it's better to do

try:
     c = IMenuItems(content)
except ComponentLookupError:
     return ''
... c used as iterable ...
return ...

than testing directly for the provided interface, as it gives an  
opportunity for an adapter to do its job. It's probably slower  
though, and maybe not a pattern generally used for marker interfaces.  
Opinions ?

Florent

-- 
Florent Guillaume, Nuxeo (Paris, France)   CTO, Director of R&D
+33 1 40 33 71 59   http://nuxeo.com   fg at nuxeo.com