Merge pull request laravel#5057 from chapeupreto/patch-6

[5.8] add documentation to `join` method on collection

Author: taylorotwell

collections.md

@@ -105,6 +105,7 @@ For the remainder of this documentation, we'll discuss each method available on
 [intersectByKeys](#method-intersectbykeys)
 [isEmpty](#method-isempty)
 [isNotEmpty](#method-isnotempty)
+[join](#method-join)
 [keyBy](#method-keyby)
 [keys](#method-keys)
 [last](#method-last)
@@ -937,6 +938,17 @@ The `isNotEmpty` method returns `true` if the collection is not empty; otherwise
 
     // false
 
+<a name="method-join"></a>
+#### `join()` {#collection-method}
+
+The `join` method joins the collection's values with a string:
+
+    collect(['a', 'b', 'c'])->join(', '); // 'a, b, c'
+    collect(['a', 'b', 'c'])->join(', ', ', and '); // 'a, b, and c'
+    collect(['a', 'b'])->join(', ', ' and '); // 'a and b'
+    collect(['a'])->join(', ', ' and '); // 'a'
+    collect([])->join(', ', ' and '); // ''
+
 <a name="method-keyby"></a>
 #### `keyBy()` {#collection-method}