aboutsummaryrefslogtreecommitdiff
path: root/node_modules/lodash/countBy.js
diff options
context:
space:
mode:
Diffstat (limited to 'node_modules/lodash/countBy.js')
-rw-r--r--node_modules/lodash/countBy.js40
1 files changed, 40 insertions, 0 deletions
diff --git a/node_modules/lodash/countBy.js b/node_modules/lodash/countBy.js
new file mode 100644
index 0000000..0e88abc
--- /dev/null
+++ b/node_modules/lodash/countBy.js
@@ -0,0 +1,40 @@
+var baseAssignValue = require('./_baseAssignValue'),
+ createAggregator = require('./_createAggregator');
+
+/** Used for built-in method references. */
+var objectProto = Object.prototype;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty = objectProto.hasOwnProperty;
+
+/**
+ * Creates an object composed of keys generated from the results of running
+ * each element of `collection` thru `iteratee`. The corresponding value of
+ * each key is the number of times the key was returned by `iteratee`. The
+ * iteratee is invoked with one argument: (value).
+ *
+ * @static
+ * @memberOf _
+ * @since 0.5.0
+ * @category Collection
+ * @param {Array|Object} collection The collection to iterate over.
+ * @param {Function} [iteratee=_.identity] The iteratee to transform keys.
+ * @returns {Object} Returns the composed aggregate object.
+ * @example
+ *
+ * _.countBy([6.1, 4.2, 6.3], Math.floor);
+ * // => { '4': 1, '6': 2 }
+ *
+ * // The `_.property` iteratee shorthand.
+ * _.countBy(['one', 'two', 'three'], 'length');
+ * // => { '3': 2, '5': 1 }
+ */
+var countBy = createAggregator(function(result, value, key) {
+ if (hasOwnProperty.call(result, key)) {
+ ++result[key];
+ } else {
+ baseAssignValue(result, key, 1);
+ }
+});
+
+module.exports = countBy;