X-Git-Url: https://git.enpas.org/?a=blobdiff_plain;f=util%2Farray.lua;h=d4ab1771111cb543db105942892005177dbbd612;hb=28c63835bdf4bfc9a8d79abba45f726caf320bb5;hp=6c1f04606642bc5cdb700f36e289a0aa655d319e;hpb=c72eea870ae98d356e03636a40f6cff16c2f6da1;p=prosody.git

diff --git a/util/array.lua b/util/array.lua
index 6c1f0460..d4ab1771 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 +9,22 @@
 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, __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 +35,15 @@ 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 +61,13 @@ 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
 
@@ -60,29 +79,42 @@ 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
 
+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(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;
 end
 
-function array_methods:reverse()
-	local len = #self-1;
-	for i=len,1,-1 do
-		self:push(self[i]);
-		self:pop(i);
-	end
-	return self;
-end
-
 function array_methods:append(array)
 	local len,len2  = #self, #array;
 	for i=1,len2 do
@@ -91,18 +123,32 @@ 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
@@ -123,7 +169,4 @@ for method, f in pairs(array_base) do
 	end
 end
 
-_G.array = array;
-module("array");
-
 return array;