parser.rb

require 'ast'

class Parser
  attr_accessor :stack
  attr_accessor :env
  attr_accessor :evaling
  def initialize(stack, words)
    @words = words
    @dec_valid = ('0'..'9').to_a + ['.'] + ['-']
    @hex_valid = ('0'..'9').to_a + ('a'..'z').to_a
    @stack = stack
    @evaling = true
    @in_string = false
  end

  def parse(token)
    new = []
    if token =~ /\".*\"/
      new.push token[1..-2]
    elsif token =~/^\".*/
      p "start of string"
      new.push token
      @evaling = false
      @in_string = true
    elsif token =~ /^.*\"/
      p "end of string"
      #Gobble up the string
      str = [token]
      temp = @stack.pop
      while (temp != "\"" and temp !~ /\".*/ and temp != nil)
        str << [temp]
        temp = @stack.pop
      end
      str << [temp]
      p str
      new.push ((str.reverse) * " ")[1..-2]
      @evaling = true
      @in_string = false
      p @in_string
    elsif @in_string
      new.push token.to_s
    elsif token == "["
      new.push "["
      @evaling = false
    elsif token == "]"
      #Gobble up the quotation
      quot = Quotation.new([])
        temp = @stack.pop
      while temp  != "["
        quot.contents.push temp
        temp = @stack.pop
      end
      quot.contents.reverse!
      new.push quot
      @evaling = true
    elsif @words[token]
      new.push @words[token]        
    elsif token.split('').all? {|c| @dec_valid.member? c }
      new.push token.to_f
    elsif token.split('0x')[1]
      new.push token.hex.to_f if token.split('0x')[1].downcase.split('').all? {|c| @hex_valid.member? c}
    elsif token.split('0b')[1]
      new.push token.to_i(2).to_f if token.split('0b')[1].downcase.split('').all? {|c| ['0','1'].member? c}
    else
      puts "ERROR: Unrecognised token"
    end
    @stack.push new
    @stack.flatten!
    return new
  end
end