On Jan 18, 6:50 am, Rushen Aly <[email protected]> wrote: > Hi everybody, > > I am studying Ruby on Rails Tutorial: Learn Rails by Example at > railstutorial.org and currently i am studying chapter 7. There are > some issues make me confused. It will be great if you help me on these > issues. > > 1). We are creating virtual attributes via attr_accessor and making it > accessible via attr_accessible. Is this statement correct? I mean if > we create a virtual attribute via attr_accessor cant we use it > without declaring it with attr_accessible?
virtual attributes don't differ from normal attributes when it comes to attr_accessible: if you've gone the whitelist approach (ie you've used attr_accessible elsewhere), then attributes (virtual or not) are protected from mass assignment unless you call attr_accessible on them. > > 2). What is the difference between self.variable and @variable? Is it > something like that we are using self.variable for variables not > mentioned in attr_accesible and @variable for variables mentioned in > attr_accesible. Is that true? > self.variable calls the method called variable (which may or may not be backed by an instance variable), whereas @variable access the instance variable of that named directly. @variable won't work for an active record attribute, since those aren't stored in individual instance variables (AR stores a hash of all the database attributes in one place( Fred > Best regards... > Rushen -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
