X-Git-Url: https://git.enpas.org/?a=blobdiff_plain;f=util%2Farray.lua;h=6c1f04606642bc5cdb700f36e289a0aa655d319e;hb=0ef23c673d1d620c9c1cc3e8aed43add63634426;hp=5b535fc19d84f74b45c98630d1db4c88f6566ccf;hpb=ad7285228de842d08f7a9abbecef7dbe8d6e3a8a;p=prosody.git diff --git a/util/array.lua b/util/array.lua index 5b535fc1..6c1f0460 100644 --- a/util/array.lua +++ b/util/array.lua @@ -1,45 +1,129 @@ +-- 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 array = {}; +local array_base = {}; local array_methods = {}; local array_mt = { __index = array_methods, __tostring = function (array) return array:concat(", "); end }; -local function array(t) +local function new_array(_, t) return setmetatable(t or {}, array_mt); end -function array_methods:map(func, t2) - local t2 = t2 or array{}; - for k,v in ipairs(self) do - t2[k] = func(v); +function array_mt.__add(a1, a2) + local res = new_array(); + return res:append(a1):append(a2); +end + +setmetatable(array, { __call = new_array }); + +function array_base.map(outa, ina, func) + for k,v in ipairs(ina) do + outa[k] = func(v); end - return t2; + return outa; end -function array_methods:filter(func, t2) - local t2 = t2 or array{}; - for k,v in ipairs(self) do +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 - t2:push(v); + outa[write] = v; + write = write + 1; end end - return t2; + + 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 -array_methods.push = table.insert; -array_methods.pop = table.remove; -array_methods.sort = table.sort; -array_methods.concat = table.concat; -array_methods.length = function (t) return #t; end - +--- These methods only mutate function array_methods:random() return self[math.random(1,#self)]; end -function array_methods:shuffle() +function array_methods:shuffle(outa, ina) 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:reverse() + local len = #self-1; + for i=len,1,-1 do + self:push(self[i]); + self:pop(i); + end + return self; end -_G.array = array +function array_methods:append(array) + local len,len2 = #self, #array; + for i=1,len2 do + self[len+i] = array[i]; + end + 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 + +--- These methods always create a new array +function array.collect(f, s, var) + local t, var = {}; + while true do + var = f(s, var); + if var == nil then break; end + table.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 + +_G.array = array; +module("array"); + +return array;