1.1 --- a/lib/__builtins__/tuple.py	Mon Jul 16 22:20:57 2018 +0200
     1.2 +++ b/lib/__builtins__/tuple.py	Mon Jul 16 23:00:47 2018 +0200
     1.3 @@ -3,7 +3,7 @@
     1.4  """
     1.5  Tuple objects.
     1.6  
     1.7 -Copyright (C) 2015, 2016, 2017 Paul Boddie <paul@boddie.org.uk>
     1.8 +Copyright (C) 2015, 2016, 2017, 2018 Paul Boddie <paul@boddie.org.uk>
     1.9  
    1.10  This program is free software; you can redistribute it and/or modify it under
    1.11  the terms of the GNU General Public License as published by the Free Software
    1.12 @@ -22,7 +22,8 @@
    1.13  from __builtins__.iteration.iterator import itemiterator
    1.14  from __builtins__.sequence import hashable, sequence
    1.15  from native import tuple_init, \
    1.16 -                   list_element, list_len, list_setsize, list_setelement
    1.17 +                   list_element, list_len, list_setsize, list_setelement, \
    1.18 +                   isinstance as _isinstance
    1.19  
    1.20  class tuple(sequence, hashable):
    1.21  
    1.22 @@ -73,7 +74,13 @@
    1.23  
    1.24          return list_len(self.__data__)
    1.25  
    1.26 -    def __add__(self, other): pass
    1.27 +    def __add__(self, other):
    1.28 +
    1.29 +        "Add this tuple to 'other'."
    1.30 +
    1.31 +        if not _isinstance(other, tuple):
    1.32 +            raise TypeError
    1.33 +        return tuple(tuplepair(self, other))
    1.34  
    1.35      def __str__(self):
    1.36  
    1.37 @@ -110,4 +117,28 @@
    1.38  
    1.39          raise TypeError
    1.40  
    1.41 +class tuplepair:
    1.42 +
    1.43 +    "A combination of tuples."
    1.44 +
    1.45 +    def __init__(self, a, b):
    1.46 +        self.a = a
    1.47 +        self.b = b
    1.48 +
    1.49 +    def __len__(self):
    1.50 +
    1.51 +        "Return the combined length of the tuples."
    1.52 +
    1.53 +        return len(self.a) + len(self.b)
    1.54 +
    1.55 +    def __getitem__(self, index):
    1.56 +
    1.57 +        "Return the value from 'index' in the combined tuple."
    1.58 +
    1.59 +        asize = len(self.a)
    1.60 +        if index < asize:
    1.61 +            return self.a.__get_single_item__(index)
    1.62 +        else:
    1.63 +            return self.b.__get_single_item__(index - asize)
    1.64 +
    1.65  # vim: tabstop=4 expandtab shiftwidth=4

     2.1 --- a/tests/tuple.py	Mon Jul 16 22:20:57 2018 +0200
     2.2 +++ b/tests/tuple.py	Mon Jul 16 23:00:47 2018 +0200
     2.3 @@ -31,3 +31,19 @@
     2.4      a, b, c = l
     2.5  except ValueError, exc:
     2.6      print "a, b, c = l: failed with length", exc.value
     2.7 +
     2.8 +# Add tuples together.
     2.9 +
    2.10 +m = ("five", 6, 7, 8)
    2.11 +n = t + m
    2.12 +print n                 # (1, 2, 3, "four", "five", 6, 7, 8)
    2.13 +
    2.14 +# Add to list, really testing tuple iteration.
    2.15 +
    2.16 +o = l + m
    2.17 +print o                 # [1, 2, 3, "four", "five", 6, 7, 8]
    2.18 +
    2.19 +try:
    2.20 +    print t + l         # should raise an exception
    2.21 +except TypeError:
    2.22 +    print "t + l: failed due to tuple-list addition"