Fwd: Re: [Zope3-Users] test() in TALES in Zope3
On Wed, 01 Feb 2006 19:15:13 +0100, "Igor Stroh" <[EMAIL PROTECTED]> said: > Michael Dudzik wrote: > > On Wed, 01 Feb 2006 09:07:17 +0100, "Andreas Jung" > [..] > >>>in Zope2 there's a test() method that can be used in TAL (*). Is there > >>>something comparable in Zope3? > >>> > >>>I know how to write such a method but how to make it available in the > >>>namespace of TALES-"python:"-expressions? I would like to write > >>>expressions like this: > >>> > >>> > >>> > >>You can write this in Python as > >> > >>condition and true_expression or false_expression > > > > > > That doesn't work under some conditions: > > > > C and A or B where C is a boolean > > > > if C is false it evaluates to B > > if C is true it evaluates to A EXCEPT when bool(A) == false > > > > example: > > > > C and None or 7 ALWAYS evaluates to 7 > > Just make it 'not C and 7 or None' :) Sure, but what about when you don't know the boolean value ahead of time, like: C and f(x) or g(x) On the other hand, (g(x), f(x))[C] works every time To be fair, both g(x) and f(x) are evaluated while f(x) if C else g(x) # python 2.5, only evaluates the appropriate function. Still, I mostly spoke up because if one starts to use an idiom like: python:C and 'somestring' or 'anotherstring' you have to realize that python:C and '' or 'anotherstring' will fail. An idiom that breaks so easily doesn't seem so useful. ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] test() in TALES in Zope3
Michael Dudzik wrote: > On Wed, 01 Feb 2006 09:07:17 +0100, "Andreas Jung" [..] >>>in Zope2 there's a test() method that can be used in TAL (*). Is there >>>something comparable in Zope3? >>> >>>I know how to write such a method but how to make it available in the >>>namespace of TALES-"python:"-expressions? I would like to write >>>expressions like this: >>> >>> >>> >>You can write this in Python as >> >>condition and true_expression or false_expression > > > That doesn't work under some conditions: > > C and A or B where C is a boolean > > if C is false it evaluates to B > if C is true it evaluates to A EXCEPT when bool(A) == false > > example: > > C and None or 7 ALWAYS evaluates to 7 Just make it 'not C and 7 or None' :) Igor ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] test() in TALES in Zope3
On Wed, 01 Feb 2006 09:07:17 +0100, "Andreas Jung" <[EMAIL PROTECTED]> said: > > > --On 1. Februar 2006 09:04:36 +0100 Frank Burkhardt <[EMAIL PROTECTED]> wrote: > > > Hi, > > > > in Zope2 there's a test() method that can be used in TAL (*). Is there > > something comparable in Zope3? > > > > I know how to write such a method but how to make it available in the > > namespace of TALES-"python:"-expressions? I would like to write > > expressions like this: > > > > > > > > You can write this in Python as > > condition and true_expression or false_expression That doesn't work under some conditions: C and A or B where C is a boolean if C is false it evaluates to B if C is true it evaluates to A EXCEPT when bool(A) == false example: C and None or 7 ALWAYS evaluates to 7 However, the expression (B,A)[C] always works if C is a boolean I'm using that until Python 2.5 comes along. ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
RE: [Zope3-Users] test() in TALES in Zope3
--On 1. Februar 2006 14:25:42 +0100 Roger Ineichen <[EMAIL PROTECTED]> wrote: Don't forget about the better overview in the project if you put application logic in view classes. (No more page template reading and macro searching for a code review) I knew that you love those kind of discussions :-) I agree mostly but there are situations where less code and less configuration is more :-) Something like test() or python: condtion and expr1 or expr2 are more or less self-explaining...no need to hide such code just for the sake of hiding it. -aj pgpW1pEzhY31R.pgp Description: PGP signature ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] test() in TALES in Zope3
Andreas Jung wrote: Frank Burkhardt <[EMAIL PROTECTED]> wrote: in Zope2 there's a test() method that can be used in TAL (*). Is there something comparable in Zope3? You can write this in Python as condition and true_expression or false_expression In Python 2.5 you'll be able to write true_expression if condition else false_expression -- Benji York Senior Software Engineer Zope Corporation ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
RE: [Zope3-Users] test() in TALES in Zope3
Hi Andreas [...] > > > > FWIW the classic Zope 3 solution is to say "Don't do that in the > > template! Do it in the view class!". I'll let others add vigor, if > > they wish. I just wanted you to know the "purist" answer in case you > > cared. ;-) > > > > If you have only one python: statement within your template > then a view > class is pretty much overhead (and a waste of manpower to write it)... > > just my 2 cents, > -aj Don't forget about the better overview in the project if you put application logic in view classes. (No more page template reading and macro searching for a code review) And there are also security related aspects. Doing to much in ZPT will force scripters to map methods to the traversal namespace and ends in accessing context attributes in ZPT like context/@@title Regards Roger Ineichen ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] test() in TALES in Zope3
On Feb 1, 2006, at 8:07 AM, Andreas Jung wrote: --On 1. Februar 2006 07:56:47 -0500 Gary Poster <[EMAIL PROTECTED]> wrote: FWIW the classic Zope 3 solution is to say "Don't do that in the template! Do it in the view class!". I'll let others add vigor, if they wish. I just wanted you to know the "purist" answer in case you cared. ;-) If you have only one python: statement within your template then a view class is pretty much overhead (and a waste of manpower to write it)... I hear ya. I figured someone ought to wave the purist flag, at least half-heartedly, though. :-) Gary ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] test() in TALES in Zope3
--On 1. Februar 2006 07:56:47 -0500 Gary Poster <[EMAIL PROTECTED]> wrote: On Feb 1, 2006, at 3:17 AM, Frank Burkhardt wrote: On Wed, Feb 01, 2006 at 09:04:36AM +0100, Frank Burkhardt wrote: [snip] Is this possible? Impressing simple solution :-) . FWIW the classic Zope 3 solution is to say "Don't do that in the template! Do it in the view class!". I'll let others add vigor, if they wish. I just wanted you to know the "purist" answer in case you cared. ;-) If you have only one python: statement within your template then a view class is pretty much overhead (and a waste of manpower to write it)... just my 2 cents, -aj pgpozO5biEJFD.pgp Description: PGP signature ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] test() in TALES in Zope3
On Feb 1, 2006, at 3:17 AM, Frank Burkhardt wrote: On Wed, Feb 01, 2006 at 09:04:36AM +0100, Frank Burkhardt wrote: [snip] Is this possible? Impressing simple solution :-) . FWIW the classic Zope 3 solution is to say "Don't do that in the template! Do it in the view class!". I'll let others add vigor, if they wish. I just wanted you to know the "purist" answer in case you cared. ;-) Gary ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] test() in TALES in Zope3
On Wed, Feb 01, 2006 at 09:04:36AM +0100, Frank Burkhardt wrote: [snip] > /> > > Is this possible? Impressing simple solution :-) . Thank you Andreas and Igor. Frank ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] test() in TALES in Zope3
Frank Burkhardt wrote: > in Zope2 there's a test() method that can be used in TAL (*). Is there > something > comparable in Zope3? > > I know how to write such a method but how to make it available in the > namespace of TALES-"python:"-expressions? I would like to write expressions > like this: > > /> HTH, Igor ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
Re: [Zope3-Users] test() in TALES in Zope3
--On 1. Februar 2006 09:04:36 +0100 Frank Burkhardt <[EMAIL PROTECTED]> wrote: Hi, in Zope2 there's a test() method that can be used in TAL (*). Is there something comparable in Zope3? I know how to write such a method but how to make it available in the namespace of TALES-"python:"-expressions? I would like to write expressions like this: You can write this in Python as condition and true_expression or false_expression -aj pgpV4jynQWzQQ.pgp Description: PGP signature ___ Zope3-users mailing list Zope3-users@zope.org http://mail.zope.org/mailman/listinfo/zope3-users
[Zope3-Users] test() in TALES in Zope3
Hi,
in Zope2 there's a test() method that can be used in TAL (*). Is there something
comparable in Zope3?
I know how to write such a method but how to make it available in the
namespace of TALES-"python:"-expressions? I would like to write expressions
like this:
Is this possible?
Regards,
Frank
(*) found it here:
http://www.zope.org/Documentation/Books/ZopeBook/2_6Edition/AdvZPT.stx
(look for 'test(' )
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