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On 28-Jan-07, at 3:56 PM, Matthew Armstrong wrote:
Setting the environment explicitly works, but that doesn't really help me write the tighter syntax that I want.  
For instance, this does allow me to use the syntax I want:

function getEnv()
    local env = {}
    local i = 1
    while true do
        local localVar, value = debug.getlocal(3, i)
        if localVar ~= nil then
            env[localVar] = value
        else
            break
        end
         i = i + 1
    end
    setmetatable(env, {__index = _G})
    return env
end

function eval(s)
    local f = assert(loadstring(s))
    setfenv(f, getEnv())
    f()
end

function flarp()
    local myLocal = "hello"  
    eval[[print(myLocal)]]
end

flarp()

(prints hello)
... but it uses the debug library and has a nice fat function call overhead. 

... and it wouldn't work if you'd written:

function flarp()
  local myLocal = "hello"
  return eval[[print(myLocal)]]
end
The simple fact of the matter is that Lua locals are ephemeral anonymous stack slots. So it's not going to work the way you want it to, I'm afraid.
(The changed flarp doesn't work because eval is tailcalled, which allows Lua to recycle the stack frame; consequently, myLocal no longer exists.)