From: jsnX <jason.dusek@...>
Date: 2007-04-19T16:15:05+09:00
Subject: Re: Recursive method not working

On Apr 18, 9:01 am, Zouplaz <u...@domain.invalid> wrote:
> def affiche_arbre(rubriques)
>      for rubrique in rubriques
>        result = '<br/>'
>        0.step(rubrique.level) { result += '&nbsp;'}
>        result += rubrique.libelle + ' ' + link_to('+', :action => 'new',
> :parent_id => rubrique) + ' '
>        unless rubrique.parent_id == nil
>          result += link_to('E', :action => 'edit', :id => rubrique) + '
> ' + link_to('D', :action => 'delete', :id => rubrique )
>        end
>        if rubrique.children.size > 0
>          result += affiche_arbre(rubrique.children)
>        end
>      end
>      "#{result}"
> end

This code could also be:
============ code ============
links(rubrique)
  [ link_to('+', :action => 'new', :parent_id => rubrique) ] +
  ( rubrique.parent_id ?
    [ link_to('E', :action => 'edit', :id => rubrique),
      link_to('D', :action => 'delete', :id => rubrique) ] : [ ] )
end

def affiche_arbre(rubriques)
  rubriques.collect do |rubrique|
    '<br/>' + ('&nbsp;' * rubrique.level) +
    [ rubrique.libelle ].concat(links(rubrique)).join(' ') +
    ( rubrique.children.size.zero? ? '' :
affiche_arbre(rubrique.children) )
  end.join()
end
=========== /code ===============
Please excuse the Anglicized new function -- I know no French. Notice
that this code allows you to test correctness of link generation
separately from correctness of the generated HTML. By restricting
myself to expressions -- there are no variable assignments in this
code, let alone mutations -- I protect myself from the kind of bug
that marred the original.