I think this is cool, ruby iterators and continuations

=begin

This might be old hat to some, but I just figured out how to make an
iterator so that if I get some kind of failure, it will return the
element and try again on the same iteration. The code below is just a
simulation, but now that I have this example working, I know how to
code what I really want. This feature of ruby really impresses me
alot !

=end

#####################################

$fail = true

$cont = nil

def proc_tab
statement = [“first statement”, “second statement”,
“third statement”]

statement.each_with_index do |stat,idx|
  if $cont
    cont = $cont
    $cont = nil
    cont.call
  end

simulate a failure on index 1

  callcc {|cont| $cont = cont } if idx == 1 and $fail
  $fail = false if $cont
  yield stat
end

end

[“searchCIO”,“searchCRM”].each do |site|
(1…5).each do |art|
$fail = true
puts site + “->” + art.to_s
proc_tab do |stat|
puts “stat:” + stat
end
end
end

On Dec 4, 1:18 pm, “[email protected][email protected] wrote:

statement.each_with_index do |stat,idx|

end

[“searchCIO”,“searchCRM”].each do |site|
(1…5).each do |art|
$fail = true
puts site + “->” + art.to_s
proc_tab do |stat|
puts “stat:” + stat
end
end
end

I’m not sure how useful it is to signal failure in the block of
proc_tab (seems like that would be something to go in the method body
instead; i.e., check the value and fix it/skip it/whatever before you
yield it to the block). But in any case, I don’t think you actually
need continuations for this…

$fail = false

class IterError < Exception; end

def proc_tab
statement = [“first statement”,
“second statement”,
“third statement”]
statement.each_index { | idx |
begin
# simulate a failure on index 1
yield statement[idx]
raise IterError if idx == 1 and $fail
rescue IterError
$fail = false
retry
end
}
end

[“searchCIO”, “searchCRM”].each { | site |
(1…5).each { | art |
$fail = true
puts site + “->” + art.to_s
proc_tab { | stat |
puts “stat:” + stat
}
}
}

Regards,
Jordan

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