Merge pull request #118 from dtgriscom/master

Added json_array_foreach(), parallelling json_object_foreach()

doc/apiref.rst

@@ -505,6 +505,35 @@ A JSON array is an ordered collection of other JSON values.
    Appends all elements in *other_array* to the end of *array*.
    Returns 0 on success and -1 on error.
 
+The following macro can be used to iterate through all elements
+in an array.
+
+.. function:: json_array_foreach(array, index, value)
+
+   Iterate over every element of ``array``, running the block
+   of code that follows each time with the proper values set to
+   variables ``index`` and ``value``, of types :type:`int` and
+   :type:`json_t *` respectively. Example::
+
+       /* array is a JSON array */
+       size_t index;
+       json_t *value;
+
+       json_array_foreach(array, index, value) {
+           /* block of code that uses index and value */
+       }
+
+   The items are returned in increasing index order.
+
+   This macro expands to an ordinary ``for`` statement upon
+   preprocessing, so its performance is equivalent to that of
+   hand-written code using the array access functions.
+   The main advantage of this macro is that it abstracts
+   away the complexity, and makes for shorter, more
+   concise code.
+
+   .. versionadded:: 2.5
+
 
 Object
 ======

src/jansson.h

@@ -148,6 +148,11 @@ int json_object_iter_set_new(json_t *object, void *iter, json_t *value);
         key && (value = json_object_iter_value(json_object_key_to_iter(key))); \
         key = json_object_iter_key(json_object_iter_next(object, json_object_key_to_iter(key))))
 
+#define json_array_foreach(array, index, value) \
+	for(index = 0; \
+		index < json_array_size(array) && (value = json_array_get(array, index)); \
+		index++)
+
 static JSON_INLINE
 int json_object_set(json_t *object, const char *key, json_t *value)
 {

test/suites/api/test_array.c

@@ -400,6 +400,25 @@ static void test_circular()
     json_decref(array1);
 }
 
+static void test_array_foreach()
+{
+    size_t index;
+    json_t *array1, *array2, *value;
+
+    array1 = json_pack("[sisisi]", "foo", 1, "bar", 2, "baz", 3);
+    array2 = json_array();
+
+    json_array_foreach(array1, index, value) {
+        json_array_append(array2, value);
+    }
+    
+    if(!json_equal(array1, array2))
+        fail("json_array_foreach failed to iterate all elements");
+
+    json_decref(array1);
+    json_decref(array2);
+}
+
 
 static void run_tests()
 {
@@ -409,4 +428,5 @@ static void run_tests()
     test_clear();
     test_extend();
     test_circular();
+    test_array_foreach();
 }

test/suites/api/test_object.c

@@ -479,7 +479,7 @@ static void test_preserve_order()
     json_decref(object);
 }
 
-static void test_foreach()
+static void test_object_foreach()
 {
     const char *key;
     json_t *object1, *object2, *value;
@@ -507,5 +507,5 @@ static void run_tests()
     test_set_nocheck();
     test_iterators();
     test_preserve_order();
-    test_foreach();
+    test_object_foreach();
 }