[Boost-users] Local_date_time constructor question

Subject: [Boost-users] Local_date_time constructor question
From: qplace (admin_at_[hidden])
Date: 2011-01-04 18:48:40

Documentation for local_date_time constructor
local_date_time(...)
  Parameters:
    date
    time_duration 
    time_zone_ptr
    bool

states that the last parameter, "The DST flag",  "must be passed to indicate 
whether the time is in daylight savings or not."

My question is: 

Isn't the combination of the first parameter, "date" and third 
parameter, "time_zone_ptr" determine if the resulted local_date_time will be 
either in the daylight saving time period or not?