Help wrapping C library in Nim using const char*

[CavariuX]

Hi, sorry for the trouble but I'm having difficulties wrapping a const char* I 
can't use cstring since the compiler complains that it's char* and not a const 
char* I have read the docs but no luck for me  Thanks in advance.

Code: 
    
    
    {.link: "libglfw.3.2.dylib".}
    
    const
      glfw3_h = "../inc/glfw3.h"
    
    proc glfwGetVersionString: cstring {.header: glfw3_h, importc: 
"glfwGetVersionString".}
    
    echo glfwGetVersionString()
    

GLFW Header 
    
    
    GLFWAPI const char* glfwGetVersionString(void);