Add array_foreach

lib/types/array.c

 /*
- * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ * SPDX-FileCopyrightText: 2018, 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -296,3 +296,19 @@ array_sort (Array      *array,
 {
     qsort (*array->data, array->length, sizeof (void *), func);
 }
+
+/**
+ * array_foreach:
+ * @array: An array
+ * @func: A function to run on each element of the array
+ *
+ * Run a function on each element of the array
+ */
+void
+array_foreach (Array       *array,
+               ForEachFunc  func,
+               void        *user_data)
+{
+    for (size_t i = 0; i < array->length; i++)
+        (*func) (array->data[i], user_data);
+}

lib/types/array.h

@@ -35,5 +35,8 @@ size_t       array_get_length   (const Array *array);
 size_t       array_get_capacity (const Array *array);
 
 // Misc
-void array_sort (Array      *array,
-                 CompareFunc func);
+void array_sort    (Array       *array,
+                    CompareFunc  func);
+void array_foreach (Array       *array,
+                    ForEachFunc  func,
+                    void        *user_data);

src/array-length.c

@@ -4,16 +4,29 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+#include <inttypes.h>
+#include <stdint.h>
 #include <stdio.h>
 
 #include <array.h>
 
+static void
+print_element (void *data,
+               void *user_data)
+{
+    printf ("%" PRIdPTR " ", (intptr_t) data);
+}
+
 static void
 print_details (Array *arr)
 {
     size_t len = array_get_length (arr);
     size_t capacity = array_get_capacity (arr);
     printf ("Array length %zu, Array capacity %zu\n", len, capacity);
+
+    printf ("Data is: ");
+    array_foreach (arr, print_element, NULL);
+    printf ("\n");
 }
 
 int
@@ -24,7 +37,7 @@ main (void)
 
     for (int i = 0; i < 10; i++)
     {
-        array_add (arr, NULL);
+        array_add (arr, (const void *) (intptr_t) i);
         print_details (arr);
     }