editline/history.h and editline/readline.h not found/working on OSX when trying to compile with developer tools installed already

Question

I am working on this tutorial on building your own LISP (http://www.buildyourownlisp.com/chapter4_interactive_prompt) and for some reason when I try to compile I get this:

Answer 1

I'm on El Capitan, Remove #include <editline/history.h>, and use cc -std=c99 -Wall test.c -ledit -o test works for me.
Add the flag -ledit before the output flad, it's a linking process, allows the compiler to directly embed calls to editline in your program. Or, you'll get the below error message,

Undefined symbols for architecture x86_64:
  "_add_history", referenced from:
      _main in prompt-086f90.o
  "_readline", referenced from:
      _main in prompt-086f90.o
ld: symbol(s) not found for architecture x86_64

Answer 2

I'm on OSX Mavericks and removing the line worked for me:

#include <editline/history.h>