Format output to 40 characters long per line

I’m fairly new to Ruby and I’ve been searching Google for a few hours now.
Does anyone know how to format the output of a print to be no more than 40 characters long?

For example:

What I want to print:

This is a simple sentence.
This simple
sentence appears
on four lines. 

But I want it formatted as:

This is a simple sentence. This simple
sentence appears on four lines.

I have each line of the original put into an array.
so x = ["This is a simple sentence.", "This simple", "sentence appears", "on three lines."]
I tried x.each { |n| print n[0..40], " " } but it didn’t seem to do anything.

Any help would be fantastic!

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  • 3 Solutions collect form web for “Format output to 40 characters long per line”

    The method word_wrap expects a Strind and makes a kind of pretty print.

    Your array is converted to a string with join("\n")

    The code:

    def word_wrap(text, line_width = 40 ) 
      return text if line_width <= 0
      text.gsub(/\n/, ' ').gsub(/(.{1,#{line_width}})(\s+|$)/, "\\1\n").strip
    end
    
    x = ["This is a simple sentence.", "This simple", "sentence appears", "on three lines."]
    
    puts word_wrap(x.join("\n"))
    x << 'a' * 50 #To show what happens with long words
    x << 'end'
    puts word_wrap(x.join("\n"))
    

    Code explanation:

    x.join("\n")) build a string, then build one long line with text.gsub(/\n/, ' ').
    In this special case this two steps could be merged: x.join(" "))

    And now the magic happens with

    gsub(/(.{1,#{line_width}})(\s+|$)/, "\\1\n")
    
    • (.{1,#{line_width}})): Take any character up to line_width characters.
    • (\s+|$): The next character must be a space or line end (in other words: the previous match may be shorter the line_width if the last character is no space.
    • "\\1\n": Take the up to 40 character long string and finish it with a newline.
    • gsub repeat the wrapping until it is finished.

    And in the end, I delete leading and trailing spaces with strip

    I added also a long word (50 a’s). What happens? The gsub does not match, the word keeps as it is.

    puts x.join(" ").scan(/(.{1,40})(?:\s|$)/m)
    

    This is a simple sentence. This simple
    sentence appears on three lines.

    Ruby 1.9 (and not overly efficient):

    >> x.join(" ").each_char.each_slice(40).to_a.map(&:join)
    => ["This is a simple sentence. This simple s", "entence appears on three lines."]
    

    The reason your solution doesn’t work is that all the individual strings are shorter than 40 characters, so n[0..40] always is the entire string.

    Ruby is the best programming language in the world - Ruby on Rails.