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-rw-r--r--util/array.lua64
1 files changed, 49 insertions, 15 deletions
diff --git a/util/array.lua b/util/array.lua
index 6c1f0460..9bf215af 100644
--- a/util/array.lua
+++ b/util/array.lua
@@ -1,7 +1,7 @@
-- 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.
--
@@ -9,12 +9,20 @@
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 pairs, ipairs = pairs, ipairs;
+local tostring = tostring;
+
local array = {};
local array_base = {};
local array_methods = {};
-local array_mt = { __index = array_methods, __tostring = function (array) return array:concat(", "); end };
+local array_mt = { __index = array_methods, __tostring = function (array) return "{"..array:concat(", ").."}"; end };
-local function new_array(_, t)
+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
@@ -25,6 +33,15 @@ end
setmetatable(array, { __call = new_array });
+-- Read-only methods
+function array_methods:random()
+ return self[math_random(1,#self)];
+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);
@@ -42,13 +59,13 @@ function array_base.filter(outa, ina, func)
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
@@ -60,15 +77,18 @@ function array_base.sort(outa, ina, ...)
return outa;
end
---- These methods only mutate
-function array_methods:random()
- return self[math.random(1,#self)];
+function array_base.pluck(outa, ina, key)
+ for i=1,#ina do
+ outa[i] = ina[i][key];
+ end
+ return outa;
end
+--- These methods only mutate the array
function array_methods:shuffle(outa, ina)
local len = #self;
for i=1,#self do
- local r = math.random(i,len);
+ local r = math_random(i,len);
self[i], self[r] = self[r], self[i];
end
return self;
@@ -91,18 +111,32 @@ function array_methods:append(array)
return self;
end
-array_methods.push = table.insert;
-array_methods.pop = table.remove;
-array_methods.concat = table.concat;
-array_methods.length = function (t) return #t; end
+function array_methods:push(x)
+ t_insert(self, x);
+ return self;
+end
+
+function array_methods:pop(x)
+ local v = self[x];
+ t_remove(self, x);
+ return v;
+end
+
+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, var = {};
+ local t = {};
while true do
var = f(s, var);
if var == nil then break; end
- table.insert(t, var);
+ t_insert(t, var);
end
return setmetatable(t, array_mt);
end