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7,723 Points

Ruby Monk

Im on Primer Ruby section 4.1 ( HASHES )

restaurant_menu = { "Ramen" => 3, "Dal Makhani" => 4, "Coffee" => 2 }
# write the each loop here. 
restaurant_menu.each do |item, price|
  restaurant_menu[item] = price + (price * 0.1)

This is what passed the section. My question is. When changing the price of a menu item by 10% , why do we call.

restaurant_menu[item] = price + (price * 0.1)

and not

restaurant_menu[price] = price + (price * 0.1)


This confuses me . Why do we have to call on the item and not the price?

2 Answers

Nelly Lam
Nelly Lam
5,098 Points

In a hash, one way to access the value of a key-value pair is this:


This just returns the value at that key.

So when you say restaurant_menu[item], you will get the price. It's similar to when you want the value inside an array, where you would write array_name[index].

But what you're doing is not just accessing the value at that key, you are assigning a new price (one that is + 10%) to that item.

7,723 Points

Ok.. I see it now. I split up the Hash into Item / Price I pull the Item part and it modifies the Value.

Duh. I totally see it now. Thank you !