merge REPL in main file rpl.rb

rpl.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require 'readline'
+
 require_relative './lib/interpreter'
 
 require_relative './lib/core/branch'
@@ -551,3 +553,48 @@ class Rpl < Interpreter
     # Graphics
   end
 end
+
+class RplRepl
+  def initialize
+    @interpreter = Rpl.new
+  end
+
+  def run
+    Readline.completion_proc = proc do |s|
+      Readline::HISTORY.grep(/^#{Regexp.escape(s)}/)
+    end
+    Readline.completion_append_character = ' '
+
+    loop do
+      input = Readline.readline( ' ', true )
+      break if input.nil? || input == 'quit'
+
+      pp Readline::HISTORY if input == 'history'
+
+      # Remove blank lines from history
+      Readline::HISTORY.pop if input.empty?
+
+      begin
+        @interpreter.run( input )
+      rescue ArgumentError => e
+        p e
+      end
+
+      print_stack
+    end
+  end
+
+  def format_element( elt )
+    @interpreter.stringify( elt )
+  end
+
+  def print_stack
+    stack_size = @interpreter.stack.size
+
+    @interpreter.stack.each_with_index do |elt, i|
+      puts "#{stack_size - i}: #{format_element( elt )}"
+    end
+  end
+end
+
+RplRepl.new.run if __FILE__ == $PROGRAM_NAME