/src/wrappers/glib/library/data_types/iterator_on_g_slist.e

 1indexing
 2	description: "Iterator for G_SLIST."
 3	copyright: "[
 4					Copyright (C) 2006 Paolo Redaelli
 5					
 6					This library is free software; you can redistribute it and/or
 7					modify it under the terms of the GNU Lesser General Public License
 8					as published by the Free Software Foundation; either version 2.1 of
 9					the License, or (at your option) any later version.
10					
11					This library is distributed in the hope that it will be useful, but
12					WITHOUT ANY WARRANTY; without even the implied warranty of
13					MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14					Lesser General Public License for more details.
15
16					You should have received a copy of the GNU Lesser General Public
17					License along with this library; if not, write to the Free Software
18					Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19					02110-1301 USA
20			]"
21
22class ITERATOR_ON_G_SLIST [ITEM->WRAPPER]
23inherit
24	ITERATOR [ITEM]
25	WRAPPER_HANDLER
26
27insert
28	GSLIST_EXTERNALS
29	GSLIST_STRUCT
30	GLOBAL_CACHE
31
32creation make
33	
34feature {} -- Creation
35	make (a_list: G_SLIST_TRAVERSABLE[ITEM]) is
36		require
37         valid_list: a_list /= Void
38		do
39			list := a_list
40		end
41	
42feature {} -- Implementation
43	list: G_SLIST_TRAVERSABLE[ITEM]
44	current_element: POINTER
45
46feature -- Iterator's features
47	start is
48		do
49			current_element := list.handle
50		end
51	
52	is_off: BOOLEAN is
53		do
54			Result:=(current_element.is_null)
55		end
56	
57	item: ITEM is
58		local
59         ptr: POINTER
60         l: WRAPPER
61		do
62			ptr := gslist_struct_get_data (current_element)
63			if ptr.is_not_null then 
64				l := wrappers.reference_at(ptr)
65				Result ?= l -- TODO: this tricks the compiler. Combining the line just above and this one seems to fail
66				if Result = Void then
67					Result := list.wrapper(ptr)
68				end
69			end
70		end
71	
72	next is
73		do
74			current_element := gslist_struct_get_next (current_element)
75		end
76end