Frameworks

[Emmanuel Surleau]

> On Oct 20, 2009, at 4:59 PM, Emmanuel Surleau wrote:
> > Compared to custom tags in, say, Mako? Having to implement a mini-
> > parser for
> > each single tag when you can write a stupid Python function is
> > needless
> > complication.
> 
> I like Mako a lot and in fact web2py template took some inspiration
> from it. Here is a mako example:
> 
> % for a in ['one', 'two', 'three', 'four', 'five']:
>      % if a[0] == 't':
>       its two or three
>      % elif a[0] == 'f':
>      four/five
>      % else:
>      ${a}
>      %endif
> % endfor
> 
> 
> Here is the same in web2py-ese, translated line by line
> 
>   {{for a in ['one', 'two', 'three', 'four', 'five']:}}
>      {{if a[0] == 't':}}
>       its two or three
>      {{elif a[0] == 'f':}}
>      four/five
>      {{else:}}
>      {{=a}}
>      {{pass}}
> {{pass}}
> 
> Legend Mako -> web2py
> % -> {{ .... }}
> endif -> pass
> endfor -> pass
> ${...} -> {{=...}}
> 
> Mako introduces terms like "endif", "endfor" which are not Python
> keywords. Web2py only uses valid python keywords.

Ingenious. Web2py looks more consistent (everything relies on {{ }} while Mako 
uses %, $ and <% >). On the other hand, the Mako syntax is a bit lighter to my 
eyes. Tradeoffs, tradeoffs...
 
> Here is another example, in Mako:
> 
> <%def name="myfunc(x)">
>      this is myfunc, x is ${x}
> </%def>
> ${myfunc(7)}
> 
> and the same in web2py
> 
> {{def myfunc(x):}}
>     this is myfunc, x is {{=x}}
> {{return}}
> {{myfunc(7)}}
> 
> Again web2py does not introduce any new syntax. only valid Python in
> {{...}} tags.
> (Notice {{myfunc(7)}} not {{=myfunc(7)}} becase the function is
> printing, we are not printing the return value of the function).
> 
> Mako needs to parse % ..., <%>...</%>, ... and ${...}. web2py needs to
> parse only {{...}}.
> 
> The use of {{...}} in web2py is inspired by Django. This has a big
> advantage over <%...%>, it is transparent to html editors and so you
> use any html editor with the templates.

Bah, as if anyone needed anything else than vim :) Just joking, I see the 
advantage if you are working with external designers.

Cheers,

Emm