1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--
local t_insert, t_sort, t_remove, t_concat
= table.insert, table.sort, table.remove, table.concat;
local setmetatable = setmetatable;
local math_random = math.random;
local math_floor = math.floor;
local pairs, ipairs = pairs, ipairs;
local tostring = tostring;
local type = type;
local array = {};
local array_base = {};
local array_methods = {};
local array_mt = {
__index = array_methods;
__name = "array";
__tostring = function (self) return "{"..self:concat(", ").."}"; end;
};
function array_mt:__freeze() return self; end
local function new_array(self, t, _s, _var)
if type(t) == "function" then -- Assume iterator
t = self.collect(t, _s, _var);
end
return setmetatable(t or {}, array_mt);
end
function array_mt.__add(a1, a2)
local res = new_array();
return res:append(a1):append(a2);
end
function array_mt.__eq(a, b)
if #a == #b then
for i = 1, #a do
if a[i] ~= b[i] then
return false;
end
end
else
return false;
end
return true;
end
function array_mt.__div(a1, func)
local a2 = new_array();
local o = 0;
for i = 1, #a1 do
local new_value = func(a1[i]);
if new_value ~= nil then
o = o + 1;
a2[o] = new_value;
end
end
return a2;
end
setmetatable(array, { __call = new_array });
-- Read-only methods
function array_methods:random()
return self[math_random(1, #self)];
end
-- Return a random value excluding the one at idx
function array_methods:random_other(idx)
local max = #self;
return self[((math.random(1, max-1)+(idx-1))%max)+1];
end
-- These methods can be called two ways:
-- array.method(existing_array, [params [, ...]]) -- Create new array for result
-- existing_array:method([params, ...]) -- Transform existing array into result
--
function array_base.map(outa, ina, func)
for k, v in ipairs(ina) do
outa[k] = func(v);
end
return outa;
end
function array_base.filter(outa, ina, func)
local inplace, start_length = ina == outa, #ina;
local write = 1;
for read = 1, start_length do
local v = ina[read];
if func(v) then
outa[write] = v;
write = write + 1;
end
end
if inplace and write <= start_length then
for i = write, start_length do
outa[i] = nil;
end
end
return outa;
end
function array_base.sort(outa, ina, ...)
if ina ~= outa then
outa:append(ina);
end
t_sort(outa, ...);
return outa;
end
function array_base.unique(outa, ina)
local seen = {};
return array_base.filter(outa, ina, function (item)
if seen[item] then
return false;
else
seen[item] = true;
return true;
end
end);
end
function array_base.pluck(outa, ina, key)
for i = 1, #ina do
outa[i] = ina[i][key];
end
return outa;
end
function array_base.reverse(outa, ina)
local len = #ina;
if ina == outa then
local middle = math_floor(len/2);
len = len + 1;
local o; -- opposite
for i = 1, middle do
o = len - i;
outa[i], outa[o] = outa[o], outa[i];
end
else
local off = len + 1;
for i = 1, len do
outa[i] = ina[off - i];
end
end
return outa;
end
--- These methods only mutate the array
function array_methods:shuffle()
local len = #self;
for i = 1, #self do
local r = math_random(i, len);
self[i], self[r] = self[r], self[i];
end
return self;
end
function array_methods:append(ina)
local len, len2 = #self, #ina;
for i = 1, len2 do
self[len+i] = ina[i];
end
return self;
end
function array_methods:push(x)
t_insert(self, x);
return self;
end
array_methods.pop = t_remove;
function array_methods:concat(sep)
return t_concat(array.map(self, tostring), sep);
end
function array_methods:length()
return #self;
end
--- These methods always create a new array
function array.collect(f, s, var)
local t = {};
while true do
var = f(s, var);
if var == nil then break; end
t_insert(t, var);
end
return setmetatable(t, array_mt);
end
---
-- Setup methods from array_base
for method, f in pairs(array_base) do
local base_method = f;
-- Setup global array method which makes new array
array[method] = function (old_a, ...)
local a = new_array();
return base_method(a, old_a, ...);
end
-- Setup per-array (mutating) method
array_methods[method] = function (self, ...)
return base_method(self, self, ...);
end
end
return array;
|
