How to get list of variable names from an erubis file?

Question

From within a Ruby script, is there a way to pragmatically obtain a list of all expected variable names and function names found in an erubis file?

For instance, how would one determine from the Eruby object that the contains the variable 'name'?

require 'erubis'
source = 'Hello, <%= name %>'
erb = Erubis::Eruby.new(source)

Answer 1

My hackish solution:

# from the original question
require 'erubis'
source = 'Hello, <%= name %>'
erb = Erubis::Eruby.new(source)

# a not so great solution
vars = {}
begin
  Erubis::Eruby.new(code).result(vars)
rescue NameError => e
  puts "Found: '#{e.name}'"
  vars[e.name.to_sym] = nil
  retry
end

Which results in:

Found: 'name'