How to Use "Puts" to the Console Without a Line Break in Ruby on Rails

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

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

How to print something without a new line in ruby

Use print instead.
You may want to follow it up by STDOUT.flush.

Ruby - Can I skip a line of input from the console and start reading from the next line?

You can read words like this:

puts 'Number of words:'
words = []
number_of_words = gets.to_i
number_of_words.times do |i|
  puts "Word #{i + 1}:"
  words << gets.chomp
end
p words

Output:

Number of words:
2
Word 1:
Hacker
Word 2:
Rank

p words
#~> [Hacker", "Rank"] 

Remove the newline after variable in `puts()` arguments

gets will include the newline character in the returned string. To remove that, you can use gets.chomp.

ROR, ruby on rails console - how to input in new line?

Leave a dangling line of code (ending a line with an operator or a comma)

puts "hello " +
  "world"

class Foo
  def this_line(is,
    unfinished)
  end
end

This won't work with MRI Ruby 1.9:

puts "hello
  world"

However, a better way of doing this would be:

puts <<-EOF
  hello
  world
EOF

Ruby Console: How to Keep 'gets' from adding a new line when the user inputs

In windows you can do it like this, otherwise you would need a similar read_char method that works in your OS

def read_char #only on windows
  require "Win32API"
  Win32API.new("crtdll", "_getch", [], "L").Call
end

def get_number
  number, inp = "", 0
  while inp != 13
    inp = read_char
    if "0123456789"[inp.chr]
      number += inp.chr
      print inp.chr  
    end
  end
  number
end

print "Enter the number of boxes: "
boxes = get_number
print " Enter number of columns to print the boxes in: "
columns = get_number
puts ""

puts "boxes: #{boxes}"
puts "columns: #{columns}"

# gives
# Enter the number of boxes: 5 Enter number of columns to print the boxes in: 6
# boxes: 5
# columns: 6

gets.chomp without moving to a new line

You can do this by using the (very poorly documented) getch:

require 'io/console'
require 'io/wait'

loop do
  chars = STDIN.getch
  chars << STDIN.getch while STDIN.ready?       # Process multi-char paste
  break if ["\r", "\n", "\r\n"].include?(chars)
  STDOUT.print chars
end

References:

• http://ruby-doc.org/stdlib-2.1.0/libdoc/io/console/rdoc/IO.html#method-i-getch
• http://ruby-doc.org/stdlib-2.1.0/libdoc/io/wait/rdoc/IO.html#method-i-ready-3F

Related follow-up question:

enter & IOError: byte oriented read for character buffered IO

My code does not work without that specific line. Why?

When entering the "+" operation, you hit two keys, + and return. Both produce a character, resulting in "+\n". (that \n is a newline character)

chomp removes the newline character.

Ruby loop create empty lines

You're calling puts x.getName(), but getName() already has puts inside of it.

puts adds a newline to the end of each argument if there is not one already.

print does not add a new line.

(What is the difference between print and puts?)

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