How to write to file when using Marshal::dump in Ruby for object serialization

binary-serialization, marshalling, ruby, serialization

Solution

Like this:

class Line
  attr_reader :p1, :p2
  def initialize point1, point2
    @p1 = point1
    @p2 = point2
  end
end

line = Line.new([1,2], [3,4])

Save `line`:

FNAME = 'my_file'

File.open(FNAME, 'wb') {|f| f.write(Marshal.dump(line))}

Retrieve into `line1`:

line1 = Marshal.load(File.binread(FNAME))

Confirm it works:

line1.p1 # => [1, 2]

Problem

Lets say I have the object line from class Line: ``` class Line def initialize point1, point2 @p1 = point1 @p2 = point2 end end ``` line = Line.new... How can I binary serialize the line object? I tried with: ``` data = Marshal::dump(line, "path/to/still/unexisting/file") ``` but it created file and didn't add anything. I read the Class: IO documentation but I couldn't really get it.

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