prawn：Prawn::Table#width

everyday Ruby 
#!/usr/bin/env ruby

require "prawn"
require "prawn/layout"

data = [["Gregory","Brown"],["James","Healy"],["Jia","Wu"]]

pdf = Prawn::Document.new

p Prawn::Table.new(data, pdf,
                   :headers => ["First Name", "Last Name"],
                   :align   => { 0 => :left, 1 => :center}).width
p Prawn::Table.new(data, pdf,
                   :headers => ["First Name First Name", "Last Name Last Name"],
                   :align   => { 0 => :left, 1 => :center}).width

で、

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