Beispielprogramme 14.1.2016

20160114/objects-1.c

+#include <stdio.h>
+
+typedef struct
+{
+  int type;
+} t_base;
+
+typedef struct
+{
+  int type;
+  int content;
+} t_integer;
+
+typedef struct
+{
+  int type;
+  char *content;
+} t_string;
+
+int main (void)
+{
+  t_integer i = { 1, 42 };
+  t_string s = { 2, "Hello, world!" };
+
+  t_base *object[] = { &i, &s };
+
+  return 0;
+}

20160114/objects-2.c

+#include <stdio.h>
+
+typedef struct
+{
+  int type;
+} t_base;
+
+typedef struct
+{
+  int type;
+  int content;
+} t_integer;
+
+typedef struct
+{
+  int type;
+  char *content;
+} t_string;
+
+int main (void)
+{
+  t_integer i = { 1, 42 };
+  t_string s = { 2, "Hello, world!" };
+
+  t_base *object[] = { (t_base *) &i, (t_base *) &s };
+
+  return 0;
+}

20160114/objects-3.c

+#include <stdio.h>
+
+typedef struct
+{
+  int type;
+} t_base;
+
+typedef struct
+{
+  int type;
+  int content;
+} t_integer;
+
+typedef struct
+{
+  int type;
+  char *content;
+} t_string;
+
+int main (void)
+{
+  t_integer i = { 1, 42 };
+  t_string s = { 2, "Hello, world!" };
+
+  t_base *object[] = { (t_base *) &i, (t_base *) &s };
+
+  for (int i = 0; i < 2; i++)
+    if (object[i]->type == 1)
+      printf ("Integer: %d\n", object[i]->content);
+    else if (object[i]->type == 2)
+      printf ("String: \"%s\"\n", object[i]->content);
+
+  return 0;
+}

20160114/objects-4.c

+#include <stdio.h>
+
+typedef struct
+{
+  int type;
+} t_base;
+
+typedef struct
+{
+  int type;
+  int content;
+} t_integer;
+
+typedef struct
+{
+  int type;
+  char *content;
+} t_string;
+
+int main (void)
+{
+  t_integer i = { 1, 42 };
+  t_string s = { 2, "Hello, world!" };
+
+  t_base *object[] = { (t_base *) &i, (t_base *) &s };
+
+  for (int i = 0; i < 2; i++)
+    if (object[i]->type == 1)
+      printf ("Integer: %d\n", (t_integer *) object[i]->content);
+    else if (object[i]->type == 2)
+      printf ("String: \"%s\"\n", (t_string *) object[i]->content);
+
+  return 0;
+}

20160114/objects-5.c

+#include <stdio.h>
+
+typedef struct
+{
+  int type;
+} t_base;
+
+typedef struct
+{
+  int type;
+  int content;
+} t_integer;
+
+typedef struct
+{
+  int type;
+  char *content;
+} t_string;
+
+int main (void)
+{
+  t_integer i = { 1, 42 };
+  t_string s = { 2, "Hello, world!" };
+
+  t_base *object[] = { (t_base *) &i, (t_base *) &s };
+
+  for (int i = 0; i < 2; i++)
+    if (object[i]->type == 1)
+      printf ("Integer: %d\n", ((t_integer *) object[i])->content);
+    else if (object[i]->type == 2)
+      printf ("String: \"%s\"\n", ((t_string *) object[i])->content);
+
+  return 0;
+}

20160114/objects-6.c

+#include <stdio.h>
+
+typedef struct
+{
+  int type;
+} t_base;
+
+typedef struct
+{
+  int type;
+  int content;
+} t_integer;
+
+typedef struct
+{
+  int type;
+  char *content;
+} t_string;
+
+int main (void)
+{
+  t_integer i = { 1, 42 };
+  t_string s = { 2, "Hello, world!" };
+
+  t_base *object[] = { (t_base *) &i, (t_base *) &s };
+
+  for (int i = 0; i < 2; i++)
+    if (object[i]->type == 2)
+      printf ("Integer: %d\n", ((t_integer *) object[i])->content);
+    else if (object[i]->type == 1)
+      printf ("String: \"%s\"\n", ((t_string *) object[i])->content);
+
+  return 0;
+}