prosody
ffe4adbd2af9
util/iterators.lua

Find changesets by keywords by author, files, the commit message, revision number or hash, or revset expression.

Software / code / prosody

Annotate

util/iterators.lua @ 13245:ffe4adbd2af9

util.array: Fix new() library function
author Kim Alvefur <zash@zash.se>
date Sat, 22 Jul 2023 16:31:05 +0200
parent 12744:e894677359e5
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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
5776
bd0ff8ae98a8 Remove all trailing whitespace
Florian Zeitz <florob@babelmonkeys.de>
parents: 5583
diff changeset
4 --
1522
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
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
11 local it = {};
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
12
5581
167c1da54606 util.iterators: Various fixes and improvements, primarily use pack() where it should be used.
Matthew Wild <mwild1@gmail.com>
parents: 5468
diff changeset
13 local t_insert = table.insert;
9688
eade1316728e util.iterators: Use pack from table.pack
Kim Alvefur <zash@zash.se>
parents: 9327
diff changeset
14 local next = next;
12589
39ae08180c81 compat: Remove handling of Lua 5.1 location of 'unpack' function
Kim Alvefur <zash@zash.se>
parents: 9688
diff changeset
15 local unpack = table.unpack;
12590
5eaf77114fdb compat: Use table.pack (there since Lua 5.2) over our util.table
Kim Alvefur <zash@zash.se>
parents: 12589
diff changeset
16 local pack = table.pack;
8797
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
17 local type = type;
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
18 local table, setmetatable = table, setmetatable;
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
19
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
20 local _ENV = nil;
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
21 --luacheck: std none
5581
167c1da54606 util.iterators: Various fixes and improvements, primarily use pack() where it should be used.
Matthew Wild <mwild1@gmail.com>
parents: 5468
diff changeset
22
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
23 -- Reverse an iterator
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
24 function it.reverse(f, s, var)
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
25 local results = {};
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
26
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
27 -- First call the normal iterator
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
28 while true do
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
29 local ret = { f(s, var) };
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
30 var = ret[1];
7351
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
31 if var == nil then break; end
5581
167c1da54606 util.iterators: Various fixes and improvements, primarily use pack() where it should be used.
Matthew Wild <mwild1@gmail.com>
parents: 5468
diff changeset
32 t_insert(results, 1, ret);
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
33 end
5776
bd0ff8ae98a8 Remove all trailing whitespace
Florian Zeitz <florob@babelmonkeys.de>
parents: 5583
diff changeset
34
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
35 -- Then return our reverse one
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
36 local i,max = 0, #results;
7260
a9ef93bc81d9 util.iterators: Variable renaming to avoid shadowing [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7258
diff changeset
37 return function (_results)
7351
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
38 if i<max then
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
39 i = i + 1;
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
40 return unpack(_results[i]);
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
41 end
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
42 end, results;
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
43 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
44
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
45 -- Iterate only over keys in a table
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
46 local function _keys_it(t, key)
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
47 return (next(t, key));
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
48 end
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
49 function it.keys(t)
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
50 return _keys_it, t;
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
51 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
52
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
53 -- Iterate only over values in a table
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
54 function it.values(t)
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
55 local key, val;
7260
a9ef93bc81d9 util.iterators: Variable renaming to avoid shadowing [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7258
diff changeset
56 return function (_t)
a9ef93bc81d9 util.iterators: Variable renaming to avoid shadowing [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7258
diff changeset
57 key, val = next(_t, key);
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
58 return val;
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
59 end, t;
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
60 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
61
7355
4b4cf0167391 util.iterators: Add iterator wrapper that works like select(n, ...) applied to original iterator
Kim Alvefur <zash@zash.se>
parents: 7351
diff changeset
62 -- Iterate over the n:th return value
4b4cf0167391 util.iterators: Add iterator wrapper that works like select(n, ...) applied to original iterator
Kim Alvefur <zash@zash.se>
parents: 7351
diff changeset
63 function it.select(n, f, s, var)
4b4cf0167391 util.iterators: Add iterator wrapper that works like select(n, ...) applied to original iterator
Kim Alvefur <zash@zash.se>
parents: 7351
diff changeset
64 return function (_s)
4b4cf0167391 util.iterators: Add iterator wrapper that works like select(n, ...) applied to original iterator
Kim Alvefur <zash@zash.se>
parents: 7351
diff changeset
65 local ret = pack(f(_s, var));
4b4cf0167391 util.iterators: Add iterator wrapper that works like select(n, ...) applied to original iterator
Kim Alvefur <zash@zash.se>
parents: 7351
diff changeset
66 var = ret[1];
4b4cf0167391 util.iterators: Add iterator wrapper that works like select(n, ...) applied to original iterator
Kim Alvefur <zash@zash.se>
parents: 7351
diff changeset
67 return ret[n];
4b4cf0167391 util.iterators: Add iterator wrapper that works like select(n, ...) applied to original iterator
Kim Alvefur <zash@zash.se>
parents: 7351
diff changeset
68 end, s, var;
4b4cf0167391 util.iterators: Add iterator wrapper that works like select(n, ...) applied to original iterator
Kim Alvefur <zash@zash.se>
parents: 7351
diff changeset
69 end
4b4cf0167391 util.iterators: Add iterator wrapper that works like select(n, ...) applied to original iterator
Kim Alvefur <zash@zash.se>
parents: 7351
diff changeset
70
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
71 -- Given an iterator, iterate only over unique items
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
72 function it.unique(f, s, var)
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
73 local set = {};
5776
bd0ff8ae98a8 Remove all trailing whitespace
Florian Zeitz <florob@babelmonkeys.de>
parents: 5583
diff changeset
74
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
75 return function ()
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
76 while true do
5581
167c1da54606 util.iterators: Various fixes and improvements, primarily use pack() where it should be used.
Matthew Wild <mwild1@gmail.com>
parents: 5468
diff changeset
77 local ret = pack(f(s, var));
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
78 var = ret[1];
7351
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
79 if var == nil then break; end
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
80 if not set[var] then
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
81 set[var] = true;
5581
167c1da54606 util.iterators: Various fixes and improvements, primarily use pack() where it should be used.
Matthew Wild <mwild1@gmail.com>
parents: 5468
diff changeset
82 return unpack(ret, 1, ret.n);
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
83 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
84 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
85 end;
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
86 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
87
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
88 --[[ Return the number of items an iterator returns ]]--
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
89 function it.count(f, s, var)
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
90 local x = 0;
5776
bd0ff8ae98a8 Remove all trailing whitespace
Florian Zeitz <florob@babelmonkeys.de>
parents: 5583
diff changeset
91
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
92 while true do
5583
78dbece77ce8 util.iterators: Small fix for variable scoping issue
Matthew Wild <mwild1@gmail.com>
parents: 5582
diff changeset
93 var = f(s, var);
7351
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
94 if var == nil then break; end
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
95 x = x + 1;
3540
bc139431830b Monster whitespace commit (beware the whitespace monster).
Waqas Hussain <waqas20@gmail.com>
parents: 3392
diff changeset
96 end
5776
bd0ff8ae98a8 Remove all trailing whitespace
Florian Zeitz <florob@babelmonkeys.de>
parents: 5583
diff changeset
97
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
98 return x;
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
99 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
100
1659
6092fc9b078b util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents: 1522
diff changeset
101 -- Return the first n items an iterator returns
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
102 function it.head(n, f, s, var)
1659
6092fc9b078b util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents: 1522
diff changeset
103 local c = 0;
7260
a9ef93bc81d9 util.iterators: Variable renaming to avoid shadowing [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7258
diff changeset
104 return function (_s, _var)
1659
6092fc9b078b util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents: 1522
diff changeset
105 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
106 return nil;
6092fc9b078b util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents: 1522
diff changeset
107 end
6092fc9b078b util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents: 1522
diff changeset
108 c = c + 1;
7260
a9ef93bc81d9 util.iterators: Variable renaming to avoid shadowing [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7258
diff changeset
109 return f(_s, _var);
7258
b8f60dd8e99a util.iterators: Return initial var from upstream iterator [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7257
diff changeset
110 end, s, var;
1659
6092fc9b078b util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents: 1522
diff changeset
111 end
6092fc9b078b util.iterators: Add head() iterator, to return the first n items
Matthew Wild <mwild1@gmail.com>
parents: 1522
diff changeset
112
3392
6e31b49c4ab8 util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents: 2923
diff changeset
113 -- Skip the first n items an iterator returns
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
114 function it.skip(n, f, s, var)
7260
a9ef93bc81d9 util.iterators: Variable renaming to avoid shadowing [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7258
diff changeset
115 for _ = 1, n do
3392
6e31b49c4ab8 util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents: 2923
diff changeset
116 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
117 end
6e31b49c4ab8 util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents: 2923
diff changeset
118 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
119 end
6e31b49c4ab8 util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents: 2923
diff changeset
120
6e31b49c4ab8 util.iterators: Add skip() to skip the first n items of an iterator
Matthew Wild <mwild1@gmail.com>
parents: 2923
diff changeset
121 -- Return the last n items an iterator returns
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
122 function it.tail(n, f, s, var)
1660
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
123 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
124 while true do
5581
167c1da54606 util.iterators: Various fixes and improvements, primarily use pack() where it should be used.
Matthew Wild <mwild1@gmail.com>
parents: 5468
diff changeset
125 local ret = pack(f(s, var));
1660
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
126 var = ret[1];
7351
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
127 if var == nil then break; end
1660
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
128 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
129 count = count + 1;
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
130 end
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
131
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
132 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
133
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
134 local pos = 0;
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
135 return function ()
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
136 pos = pos + 1;
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
137 if pos > n then return nil; end
5581
167c1da54606 util.iterators: Various fixes and improvements, primarily use pack() where it should be used.
Matthew Wild <mwild1@gmail.com>
parents: 5468
diff changeset
138 local ret = results[((count-1+pos)%n)+1];
167c1da54606 util.iterators: Various fixes and improvements, primarily use pack() where it should be used.
Matthew Wild <mwild1@gmail.com>
parents: 5468
diff changeset
139 return unpack(ret, 1, ret.n);
1660
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
140 end
5582
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
141 --return reverse(head(n, reverse(f, s, var))); -- !
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
142 end
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
143
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
144 function it.filter(filter, f, s, var)
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
145 if type(filter) ~= "function" then
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
146 local filter_value = filter;
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
147 function filter(x) return x ~= filter_value; end
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
148 end
7260
a9ef93bc81d9 util.iterators: Variable renaming to avoid shadowing [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7258
diff changeset
149 return function (_s, _var)
5582
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
150 local ret;
7260
a9ef93bc81d9 util.iterators: Variable renaming to avoid shadowing [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7258
diff changeset
151 repeat ret = pack(f(_s, _var));
7309
471189342890 util.iterators: Fix use of incorrect variable accidentally introduced in a9ef93bc81d9
Matthew Wild <mwild1@gmail.com>
parents: 7260
diff changeset
152 _var = ret[1];
471189342890 util.iterators: Fix use of incorrect variable accidentally introduced in a9ef93bc81d9
Matthew Wild <mwild1@gmail.com>
parents: 7260
diff changeset
153 until _var == nil or filter(unpack(ret, 1, ret.n));
5582
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
154 return unpack(ret, 1, ret.n);
7bc2009fdd0c util.iterators: Add filter() to run results through a filter function
Matthew Wild <mwild1@gmail.com>
parents: 5581
diff changeset
155 end, s, var;
1660
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
156 end
ae2f60a20428 util.iterators: Add tail() iterator, to return the last n items
Matthew Wild <mwild1@gmail.com>
parents: 1659
diff changeset
157
5468
2660407c3b73 util.iterators: Add ripairs() (ipairs() in reverse) (thanks Maranda)
Matthew Wild <mwild1@gmail.com>
parents: 4545
diff changeset
158 local function _ripairs_iter(t, key) if key > 1 then return key-1, t[key-1]; end end
2660407c3b73 util.iterators: Add ripairs() (ipairs() in reverse) (thanks Maranda)
Matthew Wild <mwild1@gmail.com>
parents: 4545
diff changeset
159 function it.ripairs(t)
2660407c3b73 util.iterators: Add ripairs() (ipairs() in reverse) (thanks Maranda)
Matthew Wild <mwild1@gmail.com>
parents: 4545
diff changeset
160 return _ripairs_iter, t, #t+1;
2660407c3b73 util.iterators: Add ripairs() (ipairs() in reverse) (thanks Maranda)
Matthew Wild <mwild1@gmail.com>
parents: 4545
diff changeset
161 end
2660407c3b73 util.iterators: Add ripairs() (ipairs() in reverse) (thanks Maranda)
Matthew Wild <mwild1@gmail.com>
parents: 4545
diff changeset
162
4386
ce769240f8ec util.iterators: Add range(from, to)
Matthew Wild <mwild1@gmail.com>
parents: 3540
diff changeset
163 local function _range_iter(max, curr) if curr < max then return curr + 1; end end
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
164 function it.range(x, y)
4386
ce769240f8ec util.iterators: Add range(from, to)
Matthew Wild <mwild1@gmail.com>
parents: 3540
diff changeset
165 if not y then x, y = 1, x; end -- Default to 1..x if y not given
ce769240f8ec util.iterators: Add range(from, to)
Matthew Wild <mwild1@gmail.com>
parents: 3540
diff changeset
166 return _range_iter, y, x-1;
ce769240f8ec util.iterators: Add range(from, to)
Matthew Wild <mwild1@gmail.com>
parents: 3540
diff changeset
167 end
ce769240f8ec util.iterators: Add range(from, to)
Matthew Wild <mwild1@gmail.com>
parents: 3540
diff changeset
168
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
169 -- Convert the values returned by an iterator to an array
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
170 function it.to_array(f, s, var)
7257
425bc672d60b util.iterators: Don't replace var, as we should preserve var from the original iterator [luacheck]
Matthew Wild <mwild1@gmail.com>
parents: 7186
diff changeset
171 local t = {};
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
172 while true do
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
173 var = f(s, var);
7351
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
174 if var == nil then break; end
5581
167c1da54606 util.iterators: Various fixes and improvements, primarily use pack() where it should be used.
Matthew Wild <mwild1@gmail.com>
parents: 5468
diff changeset
175 t_insert(t, var);
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
176 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
177 return t;
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
178 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
179
9327
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
180 function it.sorted_pairs(t, sort_func)
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
181 local keys = it.to_array(it.keys(t));
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
182 table.sort(keys, sort_func);
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
183 local i = 0;
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
184 return function ()
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
185 i = i + 1;
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
186 local key = keys[i];
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
187 if key ~= nil then
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
188 return key, t[key];
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
189 end
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
190 end;
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
191 end
f6f1dec164b5 util.iterators: Add sorted_pairs() method
Matthew Wild <mwild1@gmail.com>
parents: 8797
diff changeset
192
3540
bc139431830b Monster whitespace commit (beware the whitespace monster).
Waqas Hussain <waqas20@gmail.com>
parents: 3392
diff changeset
193 -- 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
194 -- and build a table
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
195 function it.to_table(f, s, var)
4441
a01b7207cb37 util.iterators: it2table: Fix variable name
Matthew Wild <mwild1@gmail.com>
parents: 4386
diff changeset
196 local t, var2 = {};
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
197 while true do
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
198 var, var2 = f(s, var);
7351
11434c46b7b7 util.iterators: Normalize indentation
Kim Alvefur <zash@zash.se>
parents: 7309
diff changeset
199 if var == nil then break; end
919
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
200 t[var] = var2;
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
201 end
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
202 return t;
75b8afb79143 util.iterators: New iterators library
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
203 end
4386
ce769240f8ec util.iterators: Add range(from, to)
Matthew Wild <mwild1@gmail.com>
parents: 3540
diff changeset
204
8797
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
205 local function _join_iter(j_s, j_var)
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
206 local iterators, current_idx = j_s[1], j_s[2];
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
207 local f, s, var = unpack(iterators[current_idx], 1, 3);
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
208 if j_var ~= nil then
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
209 var = j_var;
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
210 end
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
211 local ret = pack(f(s, var));
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
212 local var1 = ret[1];
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
213 if var1 == nil then
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
214 -- End of this iterator, advance to next
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
215 if current_idx == #iterators then
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
216 -- No more iterators, return nil
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
217 return;
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
218 end
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
219 j_s[2] = current_idx + 1;
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
220 return _join_iter(j_s);
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
221 end
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
222 return unpack(ret, 1, ret.n);
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
223 end
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
224 local join_methods = {};
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
225 local join_mt = {
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
226 __index = join_methods;
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
227 __call = function (t, s, var) --luacheck: ignore 212/t
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
228 return _join_iter(s, var);
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
229 end;
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
230 };
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
231
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
232 function join_methods:append(f, s, var)
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
233 table.insert(self, { f, s, var });
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
234 return self, { self, 1 };
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
235 end
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
236
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
237 function join_methods:prepend(f, s, var)
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
238 table.insert(self, { f, s, var }, 1);
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
239 return self, { self, 1 };
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
240 end
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
241
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
242 function it.join(f, s, var)
12744
e894677359e5 util.iterators: join: Work even with only a single iterator in the chain
Matthew Wild <mwild1@gmail.com>
parents: 12590
diff changeset
243 local t = setmetatable({ {f, s, var} }, join_mt);
e894677359e5 util.iterators: join: Work even with only a single iterator in the chain
Matthew Wild <mwild1@gmail.com>
parents: 12590
diff changeset
244 return t, { t, 1 };
8797
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
245 end
7b621a4a2e8d util.iterators: Add join() method and tests
Matthew Wild <mwild1@gmail.com>
parents: 8389
diff changeset
246
4545
c9b91ddc9c11 util.iterators: Make a standard library (no longer injects into global namespace)
Matthew Wild <mwild1@gmail.com>
parents: 4441
diff changeset
247 return it;