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Am 18.01.2014 17:45 schröbte Volodymyr Bezobiuk:

Because load() creates own local scope with no upvalues from current local
scope. You can fix this for your case with something like

for i =1,10 do  _ENV = setmetatable({ r = r }, { __index = _ENV })


Doing that will create a long lookup chain ...
Also, changing the `_ENV` upvalue of the running chunk won't change the value `load` uses as the default environment. You would need to modify the globals table stored in the registry for that (or better yet supply a custom environment in the `load` call like Dirk suggested) ... 

Philipp




On Sat, Jan 18, 2014 at 6:21 PM, H. van der Meer <H.vanderMeer@uva.nl>wrote:


Collecting function calls for example  r(3,4) in a table I would like to
execute these. But testing reveals I do something wrong.
The program in essence:

local function test(t)
local function r(a,b) return string.format(“a = %d b = %d”, a, b) end
for i =1,10 do
local f = load(t[i])
f()
end
end

This fails with error message:
/usr/local/bin/lua: [string "r(2,364)"]:1: attempt to call global 'r' (a
nil value)
stack traceback:
[string "r(2,364)"]:1: in function 'f'

What is wrong in my code? Why is function r considered global and not
found in the scope of function test(t)?

Thanks in advance
Hans van der Meer