Having trouble extending Date

Hi all,

I need to extend the Date class. Or more accurately, the ActiveSupport::CoreExtensions::date::Calculations module. Everything works fine when I include the new method in that module itself. But when I try to move the extension out of that module and into my application space (e.g., in the lib directory), I get a method not found error. I'm sure I'm missing something basic, but could sure use some help identifying what that thing is. I've tried various locations thinking that maybe I was just putting it in the wrong place, but nothing's worked. Any help's much appreciated!

Thanks, Bill

----------- calculations.rb module extension ---------------

module ActiveSupport #:nodoc:   module CoreExtensions #:nodoc:     module Date #:nodoc:       # Enables the use of time calculations within Time itself       module Calculations

         def adjust_start_for_weekends             if self.strftime('%a') == 'Fri'                return self.advance(:days => 2)             elsif self.strftime('%a') == 'Sat'                return self.advance(:days => 1)             else                return self             end          end

      end     end   end end

Maybe require it in environment.rb?

require 'calcualtions'

Alright... sorry for that first stupid answer.

You could write a special method and include it in ActiveSupport::CoreExtensions::date::Calculations but it probably won't do you any good. Without digging around too much it appears the methods in ActiveSupport::CoreExtensions::date::Calculations are being included into the Date class. Adding your special method to ActiveSupport::CoreExtensions::date::Calculations probably won't get it included in the Date class.

The solution? Include your method directly into the Date class.

#my_calculations.rb module MyCalculations   def adjust_start_for_weekends     if self.strftime('%a') == 'Fri'       return self.advance(:days => 2)     elsif self.strftime('%a') == 'Sat'       return self.advance(:days => 1)     else       return self     end   end end

Date.send :include, MyCalculations

and then require it in environment.rb

require 'my_calculations'

Hi Julian,

julian wrote:

Alright... sorry for that first stupid answer.

Not stupid at all. It got me thinking. As soon as I put a 'require' in application.rb, everything works as expected. Despite having 'said out loud' that I needed to extend the calculations module, my brain seems to have held onto the notion that I was exending the Date class. Rails picks up Class extentions automagically. We have to tell it to pick up modules. Duh ;-p

Thanks for helping me clear the 'brain fart' :wink:

Best regards, Bill

Bill Walton wrote:

----------- calculations.rb module extension ---------------

module ActiveSupport #:nodoc:   module CoreExtensions #:nodoc:     module Date #:nodoc:       # Enables the use of time calculations within Time itself       module Calculations

         def adjust_start_for_weekends             if self.strftime('%a') == 'Fri'                return self.advance(:days => 2)             elsif self.strftime('%a') == 'Sat'                return self.advance(:days => 1)             else                return self             end          end

      end     end   end end

just a quick question;   isn't "date.wday == 5" a cleaner way of saying is it friday?

don't really like strftime.

although   Date::DAYNAMES[day.wday] == "Friday"

is probably worse

Hi Matthew,

Matthew Rudy Jacobs wrote:

just a quick question;   isn't "date.wday == 5" a cleaner way of saying is it friday?

Depends on what you mean by 'cleaner' I guess. I try to write code that's understandable to anybody, not just folks who know Ruby well enough, in this case, to know what day of the week its calendar starts on. As far as that goes, I don't trust my own memory well enough to use the above without at least testing it with strftime to make sure wday == 5 is Friday :wink:

Best regards, Bill

Hi Matthew,

Matthew Rudy Jacobs wrote:

just a quick question; isn't "date.wday == 5" a cleaner way of saying is it friday?

Depends on what you mean by 'cleaner' I guess. I try to write code
that's

Until you run on a localised system where strftime returns Freitag or
something :slight_smile:

Fred

Hi Fred,

Frederick Cheung wrote:

Until you run on a localised system where strftime returns Freitag or something :slight_smile:

Very good point. The nature of "the simplest thing that could possibly work" is context-sensitive :wink:

Best regards, Bill