Changes between Version 22 and Version 23 of StandardLibraryExtensionMethods

Timestamp:

09/23/12 05:11:29 (12 years ago)

Author:

Charles

Comment:

--

StandardLibraryExtensionMethods

@@ -237 +237 @@
                 .count == old.count
 
+        extend IEnumerable
+        
+                def join(sep as String) as String
+                        """
+                        Join the items in an IEnumerable collection separated by a string.
+                        """
+                        test
+                                assert ['a', 'b'].join('.') == 'a.b'
+                                assert ['a'].join('.') == 'a'
+                                assert [1, 2].join(', ') == '1, 2'
+                                assert [1, 2].join('') == '12'
+                                assert [].join('.') == ''
+
+                def join(sep as String, lastSep as String) as String
+                        """
+                        Join the items in an IEnumerable collection with a separator string except for the last
+                        two items; join them with the lastSep string
+                        """
+                        test
+                                assert ['a', 'b'].join(', ', ' and ') == 'a and b'
+                                assert ['a', 'b', 'c'].join(', ', ' and ') == 'a, b and c'
+                                assert ['a', 'b', 'c', 'd'].join(', ', ' and ') == 'a, b, c and d'
+                                assert [1, 2, 3, 4].join(', ', ' and ') == '1, 2, 3 and 4'
+                                assert [1].join('.', ':') == '1'
+                                assert [1, 2].join('', '') == '12'
+                                assert [].join('.', ':') == ''
 
     extend IEnumerable<of T>
@@ -247 +273 @@
     
         def addRange(items as IEnumerable<of T>)
+
+                def clone as IList<of T>
+                        """
+                        Returns a new list with the contents of this list.
+                        Does not clone the contents themselves.
+                        This is sometimes known as a "shallow copy".
+                        """
+                        ensure
+                                result is not this
+                                result.count == .count
+                                result.typeOf is .typeOf
 
         def concated(other as IList<of T>?) as IList<of T>
@@ -256 +293 @@
             """
 
-        def get(flexibleIndex as int) as T
-            require
-                .count > 0
-                (flexibleIndex >= 0 and flexibleIndex < .count) _
-                    or (flexibleIndex < 0 and flexibleIndex >= -.count)
-        
-        def get(flexibleIndex as int, default as T) as T
-            ensure
-                .count == 0 implies result == default
-                (flexibleIndex > .count or flexibleIndex < -.count) _
-                    implies result == default
-    
+                def get(flexibleIndex as int) as T
+                        """
+                        Return the item at flexibleIndex. If flexibleIndex < 0 return item at flexibleIndex+.count,
+                        i.e. offset from end of list.
+                        Therefore:
+                                .get(0) returns first item in list
+                                .get(-1) returns last item
+                                .get(-2) returns second to last item
+                                .get(-.count) returns first item
+                        """
+                        require
+                                .count > 0
+                                (flexibleIndex >= 0 and flexibleIndex < .count) _
+                                        or (flexibleIndex < 0 and flexibleIndex >= -.count)
+                
+                def get(flexibleIndex as int, default as T) as T
+                        """
+                        Return item at flexibleIndex. If flexibleIndex < 0 return item at flexibleIndex+.count.
+                        Index values outside list index range return default.
+                        """     
+                        ensure
+                                .count == 0 implies result == default
+                                (flexibleIndex > .count or flexibleIndex < -.count) _
+                                        implies result == default
+
         def last as T
             """
@@ -292 +342 @@
             """
 
+                def pop as T     
+                        """ Pop value off end/top of List. """
+                        require .count > 0 
+
         def random as T
             require .count > 0
@@ -301 +355 @@
 
         def removeLast
+                        """ Remove the last item in the list. """
             require .count > 0
             ensure .count == old .count - 1