multiple escape filters for mako

[Jason]

Hello,

Using Pyramid I would like to filter expression that evaluate to None to be output as an empty string instead of "None". I have made a filter:

def none_escape(value):

    """ Returns empty string if value is None - used as Mako filter. """

    return value if value is not None else ''

and added the imports line to development.ini:

mako.imports = from sales.lib.helpers import none_escape

but when I add the filter to the default filters like this (because I still want the default html filter as well): 

mako.default_filters = h, none_escape

I get the error:

NameError: global name 'h' is not defined

This only happens when I add ", none_escape" to the default filters line. It works with just "h" and the above imports line.

Is this a bug I should be submitting, or am I missing something trivial here?

Thanks,

Jason

[Jason]

Looks like it was something trivial. I needed to format the default filters line as:

mako.default_filters =

    none_escape

    h

And they are required to be in that order. If i put them as:

mako.default_filters =

    h

    none_escape

Then none_escape was not used. In the working order I confirmed both the "h" filter and my none_escape were being used.

--

Jason

[Mike Orr]

On Thu, Jun 9, 2011 at 10:49 AM, Jason <ja...@deadtreepages.com> wrote:
> Hello,
> Using Pyramid I would like to filter expression that evaluate to None to be
> output as an empty string instead of "None". I have made a filter:
> def none_escape(value):
>     """ Returns empty string if value is None - used as Mako filter. """
>     return value if value is not None else ''

I thought we were going to patch Pyramid to do this by default ?

--
Mike Orr <slugg...@gmail.com>

[Jason]

I believe it is patched to use the html filter by default, but not escape None to an empty string. Since I am overwriting the default_filters setting I needed to speciy that I want "h" filter and my own filter.

--

Jason