'idiomatic' porting of c and or c++ code that does NULL checking

[Kagamin via Digitalmars-d-learn]

On Saturday, 23 August 2014 at 11:07:23 UTC, ketmar via 
Digitalmars-d-learn wrote:
> and "foo is null" is nice to read. ;-)

function bool init
begin
     rem Initialization flag
     bool success assign true;

     rem Initialize SDL
     if execute SDL_Init SDL_INIT_VIDEO lt 0
     begin
         execute printf "SDL could not initialize! SDL_Error: 
%s\n",
execute SDL_GetError;
         success assign false;
     end
     else
     begin
         rem Create window
         gWindow assign execute SDL_CreateWindow "SDL Tutorial",
SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH,
SCREEN_HEIGHT, SDL_WINDOW_SHOWN;
         if gWindow is NULL
         begin
             execute printf "Window could not be created! 
SDL_Error:
%s\n", execute SDL_GetError;
             success assign false;
         end
         else
         begin
             rem Get window surface
             gScreenSurface assign execute SDL_GetWindowSurface 
gWindow;
         end;
     end;

     return success;
end;

Couldn't resist... :)