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Ruby Programming
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Retry

The redo statement causes a loop to repeat the current iteration. Sometimes, though, you need to wind the loop right back to the very beginning. The retry statement is just the ticket. retry restarts any kind of iterator loop.

for i in 1..100
  print "Now at #{i}. Restart? "
  retry if gets =~ /^y/i
end

Running this interactively, you might see

Now at 1. Restart? n
Now at 2. Restart? y
Now at 1. Restart? n
 . . .

retry will reevaluate any arguments to the iterator before restarting it. The online Ruby documentation has the following example of a do-it-yourself until loop.

def doUntil(cond)
  yield
  retry unless cond
end

i = 0 doUntil(i > 3) {   print i, " "   i += 1 }
produces:
0 1 2 3 4
Ruby Programming
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