comp.lang.ruby

MonkeeSage

12/5/2007 10:28:00 AM

On Dec 4, 1:18 pm, "wbsurf...@yahoo.com" <wbsurf...@gmail.com> wrote:
> =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

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