How can I use "puts" to the console without a line break in ruby on rails?

ruby io console
Timothy T. picture Timothy T. · Feb 22, 2011 · Viewed 63.9k times · Source

I have a method which goes through a loop -- I want it to output a "." each loop so I can see it in the console. however, it puts a linebreak at the end of each when I use puts ".".

If there a way so that it just has a continuous line?

Answer

idlefingers picture idlefingers · Feb 22, 2011

You need to use print instead of puts. Also, if you want the dots to appear smoothly, you need to flush the stdout buffer after each print...

def print_and_flush(str)
  print str
  $stdout.flush
end

100.times do
  print_and_flush "."
  sleep 1
end

Edit: I was just looking into the reasoning behind flush to answer @rubyprince's comment, and realised this could be cleaned up a little by simply using $stdout.sync = true...

$stdout.sync = true

100.times do
  print "."
  sleep 1
end

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