Don't understand Paginator/Page or Ruby construct

Rails
1

Just wasted two hours trying to save the current page in the session.

My first approach was stolen from the scaffolded view:
session[:page] = @person_pages.current
But - as I discovered later - this saves a Page object, not only the
page number. To save the current page I had to use
session[:page] = @person_pages.current.number

Scaffolding generates links like:
<%= link_to ‘Previous page’,
{ :page => @person_pages.current.previous } if
@person_pages.current.previous %>
and generates a number (the page number) as action parameter.

Can someone explain shortly why the (working) code generated by
scaffolding in the view evaluates @person_pages.current.previous (a
Page object) to a number whereas @person_pages.current (also a Page
object) called in the action returns the Page object ?

Thanks,
Thomas

2

It probably does a to_s on it which returns a ‘number’.

Vish

3

On Oct 1, 2006, at 16:29, Thomas wrote:

Can someone explain shortly why the (working) code generated by
scaffolding in the view evaluates @person_pages.current.previous (a
Page object) to a number whereas @person_pages.current (also a Page
object) called in the action returns the Page object ?

Views default to calling to_s on objects to get the value to render,
hence <%= @person_pages.current %> in a view is really the return
value of @person_pages.current.to_s.

–
Jakob S. - http://mentalized.net

4

On 10/1/06, Jakob S. [email protected] wrote:

Views default to calling to_s on objects to get the value to render,
hence <%= @person_pages.current %> in a view is really the return
value of @person_pages.current.to_s.

Thank you very much.

In my opionion, it’s a bug.

With my limited experience in Rails and Ruby, I have seen the view as
“the
thing displaying my instance vars” and the code written in the view as
“another method of the controller”. Now I discover that something too
much
magic happens and the code in the views are interpreted differently, so
forcing me to remember an unnecessary detail (“remember always - coding
in
‘Controller’ or ‘View’ context ?”, “be aware when you copy/paste some
expressions”).

As the real fix (either remove to_s from Pages or the magic from the
view
interpreter) most likely will break existing code, maybe it would be
nice
when at least the scaffolder adds ‘to_s’ ?

Thomas