[Zope] Boolean

[Ross J. Reedstrom]

Jason Spisak wrote:
> 
> Zopsters:
> 
> After reading again for a boolean info the DTML docs, I can't seem to
> see the best route to test in DTML.
> I tried a simple <!--#if "foo is true"-->, didn't work
> 
> I thought, since bolean deal with 1 and 0, I'd use
> <!--#if "foo==1"--> for true and
> <!--#if "foo==0"--> for false.  That didn't work either.
> 
> If I however used blank or '' as the search criteria it worked, as in
> <!--#if "foo==''"--> for true, and nothing for false.
> 
> Whats going on with boolean, and can somebody point in the right
> direction?
>


Hmm, did you try:

<!--#if foo-->

tests for _existence_ of the property foo, and 

<!--#if "foo"-->

tests the value of foo.

so:

<!--#if foo-->
yep
<!--#else-->
nope
<!--/if-->

works regardless, but if you put in the quotes, you'll throw an error if
foo doesn't exist.


Ross
-- 
Ross J. Reedstrom, Ph.D., <reedstrm@rice.edu> 
NSBRI Research Scientist/Programmer
Computer and Information Technology Institute
Rice University, 6100 S. Main St.,  Houston, TX 77005