Ruby在同一行上多次打印

Question

Is there an easy way for Ruby to print in one line, then for the next print, it prints to the same line from the beginning.

I am trying to make a simple file counter shown on the stdout while files are being generated. It looks like a rapidly updated number at the same position on the screen.

Answer 1

could use \\r..

while(true) do
  print "\\\r"
  print "|\r"
  print "/\r"
end

Will print the char and then move the cursor back and print over it, making a little spinner like thing. Else you can look at something like curses.... (https://github.com/rkumar/rbcurse for a ruby wrapper)

Answer 2

You can try something like this:

print "Hello"
print 13.chr
print "123"

If your console supports line feed it should then replace the first chars and print "123lo". An example with a counter might look as follows:

100.times{|x| print x; print 13.chr; sleep 0.01}

Answer 3

If you're printing to a terminal-like thing you can use control characters, or curses. If you know how many items you're processing it might be easier to just make a textual progress bar, though, like wget/etc.