Software /
code /
prosody
Annotate
util/iterators.lua @ 4080:ec8184b32f60
ejabberd_init.lib.lua: Remove now needless library
author | Matthew Wild <mwild1@gmail.com> |
---|---|
date | Fri, 07 Jan 2011 03:16:39 +0000 |
parent | 3540:bc139431830b |
child | 4386:ce769240f8ec |
rev | line source |
---|---|
1522
569d58d21612
Add copyright header to those files missing one
Matthew Wild <mwild1@gmail.com>
parents:
919
diff
changeset
|
1 -- Prosody IM |
2923
b7049746bd29
Update copyright headers for 2010
Matthew Wild <mwild1@gmail.com>
parents:
1660
diff
changeset
|
2 -- Copyright (C) 2008-2010 Matthew Wild |
b7049746bd29
Update copyright headers for 2010
Matthew Wild <mwild1@gmail.com>
parents:
1660
diff
changeset
|
3 -- Copyright (C) 2008-2010 Waqas Hussain |
1522
569d58d21612
Add copyright header to those files missing one
Matthew Wild <mwild1@gmail.com>
parents:
919
diff
changeset
|
4 -- |
569d58d21612
Add copyright header to those files missing one
Matthew Wild <mwild1@gmail.com>
parents:
919
diff
changeset
|
5 -- This project is MIT/X11 licensed. Please see the |
569d58d21612
Add copyright header to those files missing one
Matthew Wild <mwild1@gmail.com>
parents:
919
diff
changeset
|
6 -- COPYING file in the source package for more information. |
569d58d21612
Add copyright header to those files missing one
Matthew Wild <mwild1@gmail.com>
parents:
919
diff
changeset
|
7 -- |
569d58d21612
Add copyright header to those files missing one
Matthew Wild <mwild1@gmail.com>
parents:
919
diff
changeset
|
8 |
919
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
9 --[[ Iterators ]]-- |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
10 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
11 -- Reverse an iterator |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
12 function reverse(f, s, var) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
13 local results = {}; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
14 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
15 -- First call the normal iterator |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
16 while true do |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
17 local ret = { f(s, var) }; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
18 var = ret[1]; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
19 if var == nil then break; end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
20 table.insert(results, 1, ret); |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
21 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
22 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
23 -- Then return our reverse one |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
24 local i,max = 0, #results; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
25 return function (results) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
26 if i<max then |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
27 i = i + 1; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
28 return unpack(results[i]); |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
29 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
30 end, results; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
31 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
32 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
33 -- Iterate only over keys in a table |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
34 local function _keys_it(t, key) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
35 return (next(t, key)); |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
36 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
37 function keys(t) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
38 return _keys_it, t; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
39 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
40 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
41 -- Iterate only over values in a table |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
42 function values(t) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
43 local key, val; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
44 return function (t) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
45 key, val = next(t, key); |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
46 return val; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
47 end, t; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
48 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
49 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
50 -- Given an iterator, iterate only over unique items |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
51 function unique(f, s, var) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
52 local set = {}; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
53 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
54 return function () |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
55 while true do |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
56 local ret = { f(s, var) }; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
57 var = ret[1]; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
58 if var == nil then break; end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
59 if not set[var] then |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
60 set[var] = true; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
61 return var; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
62 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
63 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
64 end; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
65 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
66 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
67 --[[ Return the number of items an iterator returns ]]-- |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
68 function count(f, s, var) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
69 local x = 0; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
70 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
71 while true do |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
72 local ret = { f(s, var) }; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
73 var = ret[1]; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
74 if var == nil then break; end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
75 x = x + 1; |
3540
bc139431830b
Monster whitespace commit (beware the whitespace monster).
Waqas Hussain <waqas20@gmail.com>
parents:
3392
diff
changeset
|
76 end |
919
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
77 |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
78 return x; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
79 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
80 |
1659
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
81 -- Return the first n items an iterator returns |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
82 function head(n, f, s, var) |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
83 local c = 0; |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
84 return function (s, var) |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
85 if c >= n then |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
86 return nil; |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
87 end |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
88 c = c + 1; |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
89 return f(s, var); |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
90 end, s; |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
91 end |
6092fc9b078b
util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents:
1522
diff
changeset
|
92 |
3392
6e31b49c4ab8
util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents:
2923
diff
changeset
|
93 -- Skip the first n items an iterator returns |
6e31b49c4ab8
util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents:
2923
diff
changeset
|
94 function skip(n, f, s, var) |
6e31b49c4ab8
util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents:
2923
diff
changeset
|
95 for i=1,n do |
6e31b49c4ab8
util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents:
2923
diff
changeset
|
96 var = f(s, var); |
6e31b49c4ab8
util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents:
2923
diff
changeset
|
97 end |
6e31b49c4ab8
util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents:
2923
diff
changeset
|
98 return f, s, var; |
6e31b49c4ab8
util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents:
2923
diff
changeset
|
99 end |
6e31b49c4ab8
util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents:
2923
diff
changeset
|
100 |
6e31b49c4ab8
util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents:
2923
diff
changeset
|
101 -- Return the last n items an iterator returns |
1660
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
102 function tail(n, f, s, var) |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
103 local results, count = {}, 0; |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
104 while true do |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
105 local ret = { f(s, var) }; |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
106 var = ret[1]; |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
107 if var == nil then break; end |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
108 results[(count%n)+1] = ret; |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
109 count = count + 1; |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
110 end |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
111 |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
112 if n > count then n = count; end |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
113 |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
114 local pos = 0; |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
115 return function () |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
116 pos = pos + 1; |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
117 if pos > n then return nil; end |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
118 return unpack(results[((count-1+pos)%n)+1]); |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
119 end |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
120 --return reverse(head(n, reverse(f, s, var))); |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
121 end |
ae2f60a20428
util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents:
1659
diff
changeset
|
122 |
919
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
123 -- Convert the values returned by an iterator to an array |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
124 function it2array(f, s, var) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
125 local t, var = {}; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
126 while true do |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
127 var = f(s, var); |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
128 if var == nil then break; end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
129 table.insert(t, var); |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
130 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
131 return t; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
132 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
133 |
3540
bc139431830b
Monster whitespace commit (beware the whitespace monster).
Waqas Hussain <waqas20@gmail.com>
parents:
3392
diff
changeset
|
134 -- Treat the return of an iterator as key,value pairs, |
919
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
135 -- and build a table |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
136 function it2table(f, s, var) |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
137 local t, var = {}; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
138 while true do |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
139 var, var2 = f(s, var); |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
140 if var == nil then break; end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
141 t[var] = var2; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
142 end |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
143 return t; |
75b8afb79143
util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff
changeset
|
144 end |