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lib/youplot/backends/unicode_plot.rb

@@ -1,5 +1,8 @@
 # frozen_string_literal: true
 
+# UnicodePlot - Plot your data by Unicode characters
+# https://github.com/red-data-tools/unicode_plot.rb
+
 require_relative 'processing'
 require 'unicode_plot'
 

lib/youplot/options.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 module YouPlot
+  # Command line options that are not Plot parameters
   Options = Struct.new(
     :delimiter,
     :transpose,

lib/youplot/parameters.rb

@@ -2,8 +2,7 @@
 
 module YouPlot
   # UnicodePlot parameters.
-  # * Normally in a Ruby program, you might use hash for the parameter object.
-  # * Here, I use Struct for 2 safety reason.
+  # Why Struct, not Hash?
   # * The keys are static in Struct.
   # * Struct does not conflict with keyword arguments. Hash dose.
   Parameters = Struct.new(

lib/youplot/parser.rb

@@ -4,6 +4,7 @@ require 'optparse'
 require_relative 'options'
 
 module YouPlot
+  # Class for parsing command line options
   class Parser
     class Error < StandardError; end