Documentation/tutorial-script/0008-alice-clear.patch

   1 diff --git a/rpn.c b/rpn.c
   2 --- a/rpn.c
   3 +++ b/rpn.c
   4 @@ -11,6 +11,7 @@ double val;
   5
   6  extern double pop(void);
   7  extern void push(double);
   8 +extern void clear(void);
   9
  10  extern int getsym(void);
  11
  12 @@ -53,6 +54,9 @@ int main(void)
  13                 case 'd':
  14                         pop();
  15                         break;
  16 +               case 'C':
  17 +                       clear();
  18 +                       break;
  19                 default:
  20                         fprintf(stderr, "Unknown '%c'\n", sym);
  21                         return 1;
  22 diff --git a/stack.c b/stack.c
  23 --- a/stack.c
  24 +++ b/stack.c
  25 @@ -19,3 +19,8 @@ double pop(void)
  26  {
  27         return stack[top--];
  28  }
  29 +
  30 +void clear(void)
  31 +{
  32 +       top = -1;
  33 +}