Contents

=begin
This is experimental. Please do not use it. IT WILL NOT WORK
I don't know if i will extend the work on the evaluation of formulas. 
You can access all formulas as a string and do whatever you want with this.
=end

require 'llip'
require 'llip/visitable'

class Formula
  include LLIP::Visitable

  attr_accessor :name
  attr_accessor :params
end

class Param
  include LLIP::Visitable

  attr_accessor :column_name
end

class Visitor
  def visit_formula(formula)
    puts " -- " + formula.name
    formula.params.each { |p| p.accept(self) }
  end

  def visit_param(param)
    puts " |-- " + param.column_name
  end
end

class SpreadsheetParser < LLIP::Parser
  letters = ("A".."Z").to_a.join("|")

  token :id, "(#{letters})+"

  token :"(", '\('

  token :")", '\)'

  token :"[", '['
  token :"]", ']'
  token :".", '.'

  num = (1..9).to_a.join("|")
  token :num , "(#{num})(#{num}|0)*"

  token :sep, ":"

  scope :formula

  production :formula do |p|
    p.token(:id) do |result,scanner,parser|
      result = Formula.new
      result.name = scanner.current
puts "<"+result.name+">"
      raise unless scanner.next == :"("
      raise unless scanner.next == :"["
      scanner.next
      result.params = parser.parse_params
      raise unless scanner.current == :"]"
      raise unless scanner.current == :")"
      scanner.next
      result
    end
  end

  production :params, :recursive do |p|
    p.default do |scanner, parser|
      []
    end

    p.token(:id) do |result, scanner, parser|
      param = Param.new
      param.column_name = scanner.current.to_s
      raise unless scanner.next == :"."
      raise unless scanner.next == :num
      param.column_name += scanner.current.to_s
      scanner.next
      result << param
    end

    p.token(:sep) do |result,scanner,parser|
      scanner.next
      result
    end
  end

end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
roo-0.4.0	lib/roo/spreadsheetparser.rb