Our Daily Method #19: Time#method_missing

Geplaatst door Michiel de Mare wo, 05 maa 2008 13:43:00 GMT

Our stock of cool tricks is depleted, but inspiration still strikes once in a while.

Are you using strftime a lot? Do you like writing strfime? Have you ever spelled it as strtime? strf_time? Thought it was frmtstr?

And if you spell it right, you still have to type those stupid %-signs. All in all, room for improvement.

class Time
  def method_missing(name,*args)
    if name.to_s =~ /f_/
      c = args[0] || ' '
      x = name.to_s[2..-1].split(//).
          map {|f| f =~ /[a-z]/i ? "%"+f : c}.
          join
      strftime(x)
    else
      super
    end
  end
end

So, how does it work?

It handles every method starting with f_. What follows are the characters used within strftime: Y for 4-digit year, d for day of month, etc. Underscores are converted to spaces, or to the first argument, if you provide one.

Examples:

# standard lib
Time.now.strftime("%Y%j")       #=> "2008065" 
Time.now.strftime("s")          #=> "1204725800" 
Time.now.strftime("%d %m %Y")   #=> "05 03 2008" 
Time.now.strftime("%d-%m-%Y")   #=> "05-03-2008" 
Time.now.strftime("%d %b %Y")   #=> "05 Mar 2008" 

# new and improved
Time.now.f_Yj           #=> "2008065" 
Time.now.f_s            #=> "1204725800" 
Time.now.f_d_m_Y        #=> "05 03 2008" 
Time.now.f_d_m_Y('-')   #=> "05-03-2008" 
Time.now.f_d_b_Y        #=> "05 Mar 2008" 

Cool? Stupid? Why don’t you play with it ?