I found a bug in __pairs metamethod
- From: 云风 <cloudwu@xxxxxxxxx>
- To: luajit@xxxxxxxxxxxxx
- Date: Wed, 12 Sep 2012 20:24:24 +0800
I enable "Lua 5.2 __pairs and __ipairs metamethods", and found a bug.
This is the sample code.
-------------------------
local tbl = {}
local a = { values= { foo = 1 } }
local iter = function(value)
local function loop(t,k)
return next(t,k)
end
return loop, value
end
local mt = {
__pairs = function(self)
local values = rawget(self, "values")
return iter(values)
end
}
setmetatable(a,mt)
tbl.a = a
local function trav(k,t)
if type(t) == "table" then
print(k, t)
for k,v in pairs(t) do
trav(k,v)
end
end
end
trav("",tbl)
---------------------
Run these codes above, and "a" print twice :(
table: 0x00326f48
a table: 0x00326fe0
a table: 0x00326fe0
If I change function iter to :
local iter = function(value)
return next, value
end
It will be correct. ( Only once "a" )
table: 0x002b1c38
a table: 0x002b1c60
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