/usr/share/lua/5.1/pl/Set.lua is in lua-penlight 1.2.1-1.
This file is owned by root:root, with mode 0o644.
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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 | --- A Set class.
--
-- > Set = require 'pl.Set'
-- > = Set{'one','two'} == Set{'two','one'}
-- true
-- > fruit = Set{'apple','banana','orange'}
-- > = fruit['banana']
-- true
-- > = fruit['hazelnut']
-- nil
-- > colours = Set{'red','orange','green','blue'}
-- > = fruit,colours
-- [apple,orange,banana] [blue,green,orange,red]
-- > = fruit+colours
-- [blue,green,apple,red,orange,banana]
-- > = fruit*colours
-- [orange]
--
-- Depdencies: `pl.utils`, `pl.tablex`, `pl.class`, (`pl.List` if __tostring is used)
-- @module pl.Set
local tablex = require 'pl.tablex'
local utils = require 'pl.utils'
local array_tostring, concat = utils.array_tostring, table.concat
local tmakeset,deepcompare,merge,keys,difference,tupdate = tablex.makeset,tablex.deepcompare,tablex.merge,tablex.keys,tablex.difference,tablex.update
local Map = require 'pl.Map'
local class = require 'pl.class'
local stdmt = utils.stdmt
local Set = stdmt.Set
-- the Set class --------------------
class(Map,nil,Set)
-- note: Set has _no_ methods!
Set.__index = nil
local function makeset (t)
return setmetatable(t,Set)
end
--- create a set. <br>
-- @param t may be a Set, Map or list-like table.
-- @class function
-- @name Set
function Set:_init (t)
t = t or {}
local mt = getmetatable(t)
if mt == Set or mt == Map then
for k in pairs(t) do self[k] = true end
else
for _,v in ipairs(t) do self[v] = true end
end
end
function Set:__tostring ()
return '['..concat(array_tostring(Set.values(self)),',')..']'
end
--- get a list of the values in a set.
-- @param self a Set
-- @function Set.values
Set.values = Map.keys
--- map a function over the values of a set.
-- @param self a Set
-- @param fn a function
-- @param ... extra arguments to pass to the function.
-- @return a new set
function Set.map (self,fn,...)
fn = utils.function_arg(1,fn)
local res = {}
for k in pairs(self) do
res[fn(k,...)] = true
end
return makeset(res)
end
--- union of two sets (also +).
-- @param self a Set
-- @param set another set
-- @return a new set
function Set.union (self,set)
return merge(self,set,true)
end
Set.__add = Set.union
--- intersection of two sets (also *).
-- @param self a Set
-- @param set another set
-- @return a new set
function Set.intersection (self,set)
return merge(self,set,false)
end
Set.__mul = Set.intersection
--- new set with elements in the set that are not in the other (also -).
-- @param self a Set
-- @param set another set
-- @return a new set
function Set.difference (self,set)
return difference(self,set,false)
end
Set.__sub = Set.difference
-- a new set with elements in _either_ the set _or_ other but not both (also ^).
-- @param self a Set
-- @param set another set
-- @return a new set
function Set.symmetric_difference (self,set)
return difference(self,set,true)
end
Set.__pow = Set.symmetric_difference
--- is the first set a subset of the second (also <)?.
-- @param self a Set
-- @param set another set
-- @return true or false
function Set.issubset (self,set)
for k in pairs(self) do
if not set[k] then return false end
end
return true
end
Set.__lt = Set.issubset
--- is the set empty?.
-- @param self a Set
-- @return true or false
function Set.isempty (self)
return next(self) == nil
end
--- are the sets disjoint? (no elements in common).
-- Uses naive definition, i.e. that intersection is empty
-- @param s1 a Set
-- @param s2 another set
-- @return true or false
function Set.isdisjoint (s1,s2)
return Set.isempty(Set.intersection(s1,s2))
end
--- size of this set (also # for 5.2).
-- @param s a Set
-- @return size
-- @function Set.len
Set.len = tablex.size
Set.__len = Set.len
function Set.__eq (s1,s2)
return Set.issubset(s1,s2) and Set.issubset(s2,s1)
end
return Set
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