Find out when Daylight Savings Time (DST) starts and ends using Ruby (on Rails)

Recently encountered a requirement to find out whether a particular date falls within daylight savings time. After banging my head on the wall for a few hours trying to figure it out, I found that the ruby TimeWithZone object makes this quite simple.

@mytime = Time.zone.now.in_time_zone("London")
# Creates a TimeWithZone instance (instead of just a Time instance)

@mytime.period.local_start = 2010-03-28T02:00:00+00:00 Local Standard Time 
# This is when daylight savings time starts

@mytime.period.local_end = 2010-10-31T02:00:00+00:00 Local DST 
# This is when dst ends

---------------------------------- 
@sometime = Time.parse('2010-3-27 01:00:00').in_time_zone("London") 
# 2010-03-26 16:00:00 +0000 
@sometime.period.std_offset 
# 0 
@mytime.period.local_after_start?(@sometime) 
# false 
@mytime.period.local_before_end?(@sometime) 
# true 
---------------------------------- 
@sometime = Time.parse('2010-3-29 05:00:00').in_time_zone("London") 
# 2010-03-28 21:00:00 +0100 
@sometime.period.std_offset 
# 3600 << Note that std_offset now holds the offset time for daylight savings in seconds
@mytime.period.local_after_start?(@sometime) 
# true 
@mytime.period.local_before_end?(@sometime) 
# true 
---------------------------------- 
@sometime = Time.parse('2010-12-29 05:00:00').in_time_zone("London") 
# 2010-12-28 20:00:00 +0000 
@sometime.period.std_offset 
# 0 
@mytime.period.local_after_start?(@sometime) 
# true 
@mytime.period.local_before_end?(@sometime) 
# false 

Sometimes I feel like killing Aptana...

I'm probably doing something stupid, but always seem to lose my project files in Aptana. "You attempted to go into a closed project" it tells me. Well, Aptana, if you show me the folder list I can probably open the project so I can go into it. But no, you have to make this such a challenge every time. The solution for me, it turns out, is to

1. Go to my Ruby Explorer
2. Right click on the empty window
3. Select "open project"
4. Open whatever project Aptana is insisting I want to get into.
5. Go back to the Project Tree
6. Keep clicking the "Go Up" icon to reveal the entire workspace

Another 20 minutes spent tearing my hair out...

collection_select の値を rjs に渡す

備忘録

<%= f.collection_select(:something , Company.find(:all), :id, :name, 
  {},
  {:onchange => remote_function(:url => {:action => "change_vendor"}, :with => "'id='+this.value")}
 )%> 

:with で含めた値がパラメータとして渡されます。