try: for-loop

[BlueShadow]

Hi I like to put a for-loop in a try except clause in an html file.
My problem is that the pass from the for loop terminates the try block.

{{try:}}
{{for x in db.test}}
{{=x.title}}
{{pass}}
{{except:}}
no database entries
{{pass}}

[Bruno Rocha]

I think you should not do this, do this kinf of logic on controller, model or module.

--

Bruno Rocha

[http://rochacbruno.com.br]

[Niphlod]

didn't test it, but I spot a missing : after "for x in db.test"

[Niphlod]

btw, this works perfectly as intended....

trying to do 1/0
{{try:}}
{{for a in range(15):}}
    {{=1/0}}
{{pass}}
{{except:}}
    can't divide by 0
{{pass}}

[BlueShadow]

I tried it too and for some weird reason it works.
The missing doublepoint you spotted is in my complete code on my server^^
what I really want to do is: diyplaying a database entry in a table.
this entry varies from no entries to about 10.
I didn't account for the no entries part but I got a bunch of error messages in my log which result from this for loop which is going through the entries Titles if there are none it still requests the tile and crashes
so
this is more close to my code:

<table>
{{for z in articles:}}
<TR><TD>{{=z.Title}} </TD><TD> {{=A(z.Title,_href=URL(r=request,f='article',vars=dict(id=z.id)))}}</TD></TR>
{{pass}}
<\table>

Now what I want is to skip this loop and display a static message if there are no articles



Am Mittwoch, 30. Mai 2012 16:19:32 UTC+2 schrieb Niphlod:btw, this works perfectly as intended....

trying to do 1/0
{{try:}}
{{for a in range(15):}}
    {{=1/0}}
{{pass}}
{{except:}}
    can't divide by 0
{{pass}}

Il giorno mercoledì 30 maggio 2012 16:15:10 UTC+2, Niphlod ha scritto:
didn't test it, but I spot a missing : after "for x in db.test"

Il giorno mercoledì 30 maggio 2012 16:08:10 UTC+2, BlueShadow ha scritto:Hi I like to put a for-loop in a try except clause in an html file.

[Niphlod]

.... you're overcomplicating a small issue

{{if articles and len(articles)>0:}}
display whatever you want in a for loop
{{else:}}
display your static message
{{pass}}

[BlueShadow]

OK it obviously has nothing to do with the for loop in try except because the for loop finishes when there are no entries in articles. But some basic understanding of python should have told me the solution^^
thats what works if anyone is interested:
{{try:}}
{{print article[0].title}}
{{empty=0}}
{{except:}}
{{empty=1}}
{{pass}}
{{if empty==0}}
#for loop
{{else:}}
static message
{{pass}}

[Bruno Rocha]

len(articles) is not necessary

{{if articles:}}

display whatever you want in a for loop
{{else:}}
display your static message
{{pass}}

On Wed, May 30, 2012 at 12:04 PM, Niphlod <nip...@gmail.com> wrote:

{{if articles and len(articles)>0:}}
display whatever you want in a for loop
{{else:}}
display your static message
{{pass}}

[BlueShadow]

thats even more elegant^^

[Niphlod]

uhm, depends.... if he uses lists and articles is = [], there will be a problem.....
Anyway, under some circumstances you're right.

[Anthony]

On Wednesday, May 30, 2012 11:59:13 AM UTC-4, Niphlod wrote:

uhm, depends.... if he uses lists and articles is = [], there will be a problem.....

What problem? An empty list evaluates to False.

Anthony 

[Niphlod]

I am astonished... I missed this in almost 3 years of python development :D

I genuinely repent and knee before you, Anthony ....

Niphlod

[Doug Philips]

BTW: Take a look at the Style Guide for Python Code (PEP-8) for lots
of really helpful tips.
The empty collections (of which list is one) can be found under
Programming Recommendations of PEP-8:
http://www.python.org/dev/peps/pep-0008/#programming-recommendations

--Doug