abusing of local_variable_get

easy_printf.rb

require './variable_table_of_caller'

def easy_printf(template)
  keys = template.scan(/%{(.+?)}/).flatten.map(&:to_sym)
  printf(template, variable_table_of_caller_with_level(2, *keys))
end

if $0 == __FILE__
  foo = 1
  bar = 'baz'

  # normal:
  # printf("%{foo}, %{bar}\n", foo: foo, bar: bar)

  easy_printf("%{foo}, %{bar}\n") #=> 1, baz
end

variable_table_of_caller.rb

require 'binding_of_caller'

def variable_table_of_caller_with_level(level, *names)
  bind = binding.of_caller(level)
  names.map do |name|
    [name, bind.local_variable_get(name)]
  end.to_h
end
  
def variable_table_of_caller(*names)
  variable_table_of_caller_with_level(2, *names)
end


if $0 == __FILE__
  x = 1
  foo = 'bar'
  o = Object.new

  p variable_table_of_caller(*%i[x foo o]) #=> {:x=>1, :foo=>"bar", :o=>#<Object:0x00000001ead188>}
end