Kernel.defp

You're seeing just the macro defp, go back to Kernel module for more information.
Link to this macro

defp(call, expr \\ nil)

View Source (macro)

Defines a private function with the given name and body.

Private functions are only accessible from within the module in which they are defined. Trying to access a private function from outside the module it's defined in results in an UndefinedFunctionError exception.

Check def/2 for more information.

Examples

defmodule Foo do
  def bar do
    sum(1, 2)
  end

  defp sum(a, b), do: a + b
end

Foo.bar()
#=> 3

Foo.sum(1, 2)
** (UndefinedFunctionError) undefined function Foo.sum/2