There are three ways to print out line numbers.
Lets print all three in test.rb

LINE
caller()
caller_locations(1,1)

caller_locations or LINE will be the decision on which to implement. Lets figure out how all of that works :+1 in production.rb

checklist

1. make sure the functionality is modular (callable from a method).

These definitions must be understood:
Function Definition vs Prototype/Function Declaration vs Calling the Function

Dont forget the Overarching goal #1

it should "print line number, var name, and var value"

line 10, testB, val 5 || line 11, testB, val 4 || line 10, testB, val 6 || line 11, testB, val 4

line 20, testC, val 2 || line 21, testD, val 3

line 24, testB, val 2

end