print.c

   1 #include <stdio.h>
   2 #include "lambda.h"
   3
   4 #define PRINT_ABS(t) {\
   5         if(t->data.abstraction.strict)\
   6                 putchar('!');\
   7         printf("%s", t->data.abstraction.ident);\
   8         }
   9
  10
  11 void term_print(struct lambda *t, struct lambda *mark)
  12 {
  13         if(t == mark)
  14                 putchar('|');
  15         switch(t->which){
  16         case lambda_ident:
  17                 printf("%s", t->data.identifier.ident);
  18                 break;
  19         case lambda_abs:
  20                 printf("λ");
  21                 PRINT_ABS(t);
  22                 while((t = t->data.abstraction.expr)->which == lambda_abs){
  23                         putchar(' ');
  24                         PRINT_ABS(t);
  25                 }
  26                 putchar('.');
  27                 term_print(t, mark);
  28                 break;
  29         case lambda_app:
  30                 if(t->data.application.expr1->which == lambda_abs)
  31                         putchar('(');
  32                 term_print(t->data.application.expr1, mark);
  33                 if(t->data.application.expr1->which == lambda_abs)
  34                         putchar(')');
  35
  36                 putchar(' ');
  37
  38                 if(t->data.application.expr2->which == lambda_abs)
  39                         putchar('(');
  40                 term_print(t->data.application.expr2, mark);
  41                 if(t->data.application.expr2->which == lambda_abs)
  42                         putchar(')');
  43                 break;
  44         }
  45         if(t == mark)
  46                 putchar('|');
  47 }
  48
  49 void lambda_print(struct lambda *t, struct lambda *mark)
  50 {
  51         term_print(t, mark);
  52         putchar('\n');
  53 }