rpl.rb/repl.rb
2021-11-18 15:44:09 +01:00

60 lines
1.3 KiB
Ruby

# coding: utf-8
# frozen_string_literal: true
require 'readline'
require './lib/core'
require './lib/dictionary'
require './lib/parser'
require './lib/runner'
module Rpn
class Repl
def initialize
@stack = []
@dictionary = Dictionary.new
@parser = Parser.new
@runner = Runner.new
Rpn::Core.init
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'
input = '"rpn.rb version 0.0"' if %w[version uname].include?( input )
# Remove blank lines from history
Readline::HISTORY.pop if input.empty?
@stack, @dictionary = @runner.run_input( @stack, @dictionary,
@parser.parse_input( input ) )
print_stack
end
end
def format_element( elt )
elt[:value]
end
def print_stack
stack_size = @stack.size
@stack.each_with_index do |elt, i|
puts "#{stack_size - i}: #{format_element( elt )}"
end
end
end
end
Rpn::Repl.new.run