############################################################################
#
#	Name:	shuffile.icn
#
#	Title:	Shuffle lines in a file
#
#	Author:	Ralph E. Griswold
#
#	Date:	June 10, 1988
#
############################################################################
#  
#     This program writes a version of the input file with the lines
#  shuffled.  For example, the result of shuffling
#  
#                   On the Future!-how it tells
#                   Of the rapture that impells
#                  To the swinging and the ringing
#                   Of the bells, bells, bells-
#                Of the bells, bells, bells, bells,
#                          Bells, bells, bells-
#            To the rhyming and the chiming of the bells!
#  
#  is
#  
#            To the rhyming and the chiming of the bells!
#                  To the swinging and the ringing
#                          Bells, bells, bells-
#                   Of the bells, bells, bells-
#                   On the Future!-how it tells
#                Of the bells, bells, bells, bells,
#                   Of the rapture that impells
#  
#  Option: The option -s n sets the seed for random generation to n.
#  The default seed is 0.
#  
#  Limitation:
#
#     This program stores the input file in memory and
#  shuffles pointers to the lines; there must be enough memory
#  available to store the entire file.
#  
############################################################################
#
#  Links: options, shuffle
#
############################################################################

link options, shuffle

procedure main(args)
   local opts, a

   opts := options(args, "s+")
   &random := \opts["s"]

   a := []
   every put(a,!&input)
   every write(!shuffle(a))
end