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Ruby

Posted by Rohit Begani
Rohit Begani
5,614 Points

Problems with a code I wrote

I have written this code for a simple library managment course. Here I want to do 2 things which I have not been able to do:

  1. I want the program to throw an ArgumentError if the price < 0 or if isbn is empty. I have done that but isn't there a way to do it using raise_error which I guess is the correct way.
  2. I want the price to be displayed with precision of 2. I can't do that also though I have tried to with sprintf Any help would be highly appreciated

CODE

class BookInStock
attr_reader :isbn, :price

def initialize(isbn = 0, price = "")
@isbn = isbn
@price = price
sprintf("%.2f" % @price)
end

def isbn=(isbn)
@isbn=isbn;
end

def isbn()
@isbn;
end

def price=(price)
number_with_precision(price, :precision => 2)
#sprintf("%.2f" % @price.to_f)
@price=price;
end

def price()
@price
end

def price_as_string
raise ArgumentError unless price > 0 
raise ArgumentError if isbn == "" 
#sprintf("%.2f" % @price)
#val = 9.756
#sprintf("%.2f" % val)
#print "#{val}"
puts "$#{price} #{isbn}"
return price
end
end

book_in = BookInStock.new('', 25.00)
book_in.class

book_in.price_as_string