Add a new example of the new M_LET feature.

example/ex-string03.c

@@ -0,0 +1,40 @@
+#include <stdio.h>
+#include "m-string.h"
+#include "m-dict.h"
+#include "m-array.h"
+
+/* Definition of an associative map string_t --> size_t */
+DICT_DEF2(dict_str, string_t, size_t)
+#define M_OPL_dict_str_t() DICT_OPLIST(dict_str, STRING_OPLIST, M_DEFAULT_OPLIST)
+
+/* Definition of an array of string_t */
+ARRAY_DEF(vector_str, string_t)
+#define M_OPL_vector_str_t() ARRAY_OPLIST(vector_str, STRING_OPLIST)
+
+int main(void)
+{
+    // Construct an array of string, performing a convertion of the C const char *
+    // into a proper string_t at real time and push then into a dynamic array
+    // that is declared, initialized and cleared.
+    M_LET( (words, ("This"), ("is"), ("a"), ("useless"), ("sentence"), ("."),
+                    ("It"), ("is"), ("used"), ("a"), ("bit"), ("to"), ("count"), ("words"), (".") ),
+                    vector_str_t) {
+        // Print the arrays.
+        printf("The words are: ");
+        vector_str_out_str(stdout, words);
+        printf("\n");
+
+        // Count the words.
+        M_LET(map, dict_str_t) {
+            // Count the words:
+            for M_EACH(w, words, vector_str_t) {
+                (*dict_str_get_at(map, *w)) ++;
+            }
+
+            // Print the count:
+            for M_EACH(p, map, dict_str_t) {
+                printf ("%zu occurences of %s\n", p->value, string_get_cstr(p->key));
+            }
+        }
+    }
+}