Rails - Aug 2008 - avoiding exceptions in views

when rendering a view, if the object being rendered doesn''t respond to
a
method it raises an error message.
For example, I have an Employee class and each employee has many Tasks.
So I may call:
<%= employee.tasks.first.task_name %>

If, for some reason an employee has 0 tasks associated with it, the
above template method would raise an exception.
Is it efficient to loop through the @employees array, with something
like:

@employees = Employee.find(:all,...).collect{|e| e if e.tasks.size >
0}.compact

or is there a better way?

thanks for reading.
-- 
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Oliver Fox wrote:
> <%= employee.tasks.first.task_name %>
> 
> If, for some reason an employee has 0 tasks associated with it, the
...
> @employees = Employee.find(:all,...).collect{|e| e if e.tasks.size >
> 0}.compact
Your controller is not controlling your view enough! To present only employees 
with tasks, try this abomination:

  Employee.find(:all).select{|e| e.tasks.any? }

That''s the same as yours, but it uses select.

If that melts your database server, try some variation on:

  Employee.find(:all, :include => :tasks,
                 :conditions => ''tasks.id is not null'')

There might be better or alternate ways. Another one is this:

   <%= (employee.tasks + [Task.new]).first.task_name %>

Then at least the .first-ed array always has a blank Task on the end with a 
blank .name. You didn''t specify if your view should view taskless
employees.
(And shame on them for slacking!!;)

-- 
   Phlip


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