Assign one field from a embebed list value to another element?

Hi, I have a list for collection:

{
       name: "orange",
       price: NumberDecimal("4.99"),
       discountPrice: NumberDecimal("3.99"),
       newPrice: NumberDecimal("3.99"),
       oldPrices:[
            {
               id: 1,
               reason: "normalChange",
               type: "price",
               info: NumberDecimal("4.99")
            },
            {
               id: 2,
               reason: "normalChange",
               type: "price",
               info: NumberDecimal("3.99")
            },
            {
               id: 3,
               reason: "offer",
               type: "price",
               info: NumberDecimal("2.99")
            },
            {
               id: 4,
               reason: "normalChange",
               type: "price",
               info: NumberDecimal("4.50")
            },
       ]
  } ,
{
       name: "bannana",
       price: NumberDecimal("1.99"),
       discountPrice: NumberDecimal("1.49"),
       newPrice: NumberDecimal("1.39"),
       oldPrices:[
            {
               id: 1,
               reason: "normalChange",
               type: "price",
               info: NumberDecimal("24.99")
            },
            {
               id: 2,
               reason: "normalChange",
               type: "price",
               info: NumberDecimal("1.99")
            },
            {
               id: 3,
               reason: "offer",
               type: "price",
               info: NumberDecimal("2.99")
            }           
       ]
  }    
  

I want assign the last “info” value from the “oldPrices” that said “normalChange” at price,
in this answer:

Answer

I saw I can set a value from another element to another, but my problem is that I will not know which position of the array is the last value so i have to look for it. Could you help me with that? Thz

Take a look at $last.