I also found this on stackoverflow: http://stackoverflow.com/questions/3835170/ruby-assignment-and-comparison-in-one-line
On Feb 14, 5:18 pm, Kai Middleton <kai.middle...@gmail.com> wrote: > I was looking at this bit of code within Rails: > > # File actionpack/lib/action_controller/metal/flash.rb, line 12 > def redirect_to(options = {}, response_status_and_flash = {}) #:doc: > if alert = response_status_and_flash.delete(:alert) > flash[:alert] = alert > end > > if notice = response_status_and_flash.delete(:notice) > flash[:notice] = notice > end > > if other_flashes = response_status_and_flash.delete(:flash) > flash.update(other_flashes) > end > > super(options, response_status_and_flash) > end > > And I thought: ouch, aren't those supposed to be double-equals? Well, > no, it's an assignment within an if statement. It saves a line of > code per usage, thus three lines of code in that method. > > But I thought: wow, that sure violates the principle of least > surprise. Perhaps it would be nice if there were a way to reference > the most recent if-expression. I recall how a lone underscore in irb > will contain the value of whatever was last evaluated. So perhaps > something like this would be nice: > > if response_status_and_flash.delete(:notice) > flash[:notice] = _ > end > > instead of what we see above: > > if notice = response_status_and_flash.delete(:notice) > flash[:notice] = notice > end -- 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 rubyonrails-talk@googlegroups.com. To unsubscribe from this group, send email to rubyonrails-talk+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.