# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1485645532 -3600
# Node ID 360560918d918a58cb1775ae83234ff7dc639900
# Parent  626c0f5435707544920c0056af370b49f435c4ae
Implemented list pop and addition methods.

diff -r 626c0f543570 -r 360560918d91 lib/__builtins__/list.py
--- a/lib/__builtins__/list.py	Sat Jan 28 23:32:15 2017 +0100
+++ b/lib/__builtins__/list.py	Sun Jan 29 00:18:52 2017 +0100
@@ -3,7 +3,7 @@
 """
 List objects.
 
-Copyright (C) 2015, 2016 Paul Boddie <paul@boddie.org.uk>
+Copyright (C) 2015, 2016, 2017 Paul Boddie <paul@boddie.org.uk>
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -22,7 +22,7 @@
 from __builtins__.iterator import itemiterator
 from __builtins__.sequence import sequence
 from native import list_append, list_concat, list_element, list_init, \
-                   list_len, list_nonempty, list_setelement
+                   list_len, list_nonempty, list_setelement, list_setsize
 
 class list(sequence):
 
@@ -59,8 +59,19 @@
         for i in iterable:
             self.append(i)
 
-    def pop(self): pass
+    def pop(self):
+
+        "Remove the last item from the list, returning the item."
+
+        i = self[-1]
+
+        # NOTE: Should truncate the allocated list after several pops.
+
+        list_setsize(self.__data__, self.__len__() - 1)
+        return i
+
     def reverse(self): pass
+
     def sort(self, cmp=None, key=None, reverse=0): pass
 
     def __len__(self):
@@ -69,7 +80,13 @@
 
         return list_len(self.__data__)
 
-    def __add__(self, other): pass
+    def __add__(self, other):
+
+        "Add this list to 'other', producing a new list."
+
+        l = list(self)
+        l.extend(other)
+        return l
 
     def __iadd__(self, other):
 
diff -r 626c0f543570 -r 360560918d91 tests/list.py
--- a/tests/list.py	Sat Jan 28 23:32:15 2017 +0100
+++ b/tests/list.py	Sun Jan 29 00:18:52 2017 +0100
@@ -42,5 +42,28 @@
 except ValueError, exc:
     print "l.index(4): failed to find argument", exc.value
 
+# Test equality.
+
 print l == [1, 2, 3]         # False
 print l == [1, 2, 3, "four"] # True
+
+# Test concatenation.
+
+a = [1, 2]
+a += [3, 4]
+print a                 # [1, 2, 3, 4]
+
+b = [5, 6]
+c = a + b
+print c                 # [1, 2, 3, 4, 5, 6]
+
+# Test removal.
+
+print c.pop()           # 6
+print c                 # [1, 2, 3, 4, 5]
+
+d = []
+try:
+    d.pop()             # should raise an exception
+except IndexError, exc:
+    print "d.pop(): failed to access item", exc.index