diff options
| -rw-r--r-- | util/set.lua | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/util/set.lua b/util/set.lua index 02fabc6a..b7345e7e 100644 --- a/util/set.lua +++ b/util/set.lua @@ -6,8 +6,8 @@ -- COPYING file in the source package for more information. -- -local ipairs, pairs, setmetatable, next, tostring = - ipairs, pairs, setmetatable, next, tostring; +local ipairs, pairs, getmetatable, setmetatable, next, tostring = + ipairs, pairs, getmetatable, setmetatable, next, tostring; local t_concat = table.concat; local _ENV = nil; @@ -31,6 +31,11 @@ function set_mt:__freeze() return a; end +local function is_set(o) + local mt = getmetatable(o); + return mt == set_mt; +end + local function new(list) local items = setmetatable({}, items_mt); local set = { _items = items }; @@ -171,6 +176,7 @@ end return { new = new; + is_set = is_set; union = union; difference = difference; intersection = intersection; |