get function from coroutine

say there is a coroutine C created from the function F:

C = coroutine.create(F)

is there any way to get the function F, given only the coroutine C?

You are setting C to equal the coroutine of F, am I correct? So arent you getting the function F if you declare C? Trick question?

I'm fairly certain that what you're asking is impossible. Why do you ask?

i would like to implement the UNIX fork function:

function fork()

local C = coroutine.running()

local F = someMagic(C)

local C_child = coroutine.create(F)

passCoroutineBackToScheduler(C_child)

end

or something similar such that one simply has to call fork to branch into two coroutines

Why not simply store the function in a table upon using coroutine create - perhaps use function overwriting?

coroutine.native = {} for i,v in pairs(coroutine) do if type(v) == "function" then coroutine.native[i] = v end end

coroutine.active = {}
coroutine.create = function(...)
  table.insert(coroutine.active, {...})
  return {#coroutine.active, coroutine.native.create(...)}
end

coroutine.resume = function(co, ...)
  return coroutine.native.resume(co[2],...)
end

--#Reimplement other coroutine functions here

function fork()
  local c = coroutine.running()
  local f = coroutine.active[1][c[1]]
  local c_child = coroutine.create(f)
  passCoroutineBackToScheduler(c_child)
end

Not tested, but you get the idea. Of course, if you wanted to get the function of any coroutine created before running this code, that is still impossible. However for most purposes I think this would work fine.

jay5476, on 26 November 2013 - 03:32 PM said:

Couldn't you just do something like this

oldCreate = coroutine.create
function coroutine.create(func)
  local t = oldCreate(func)
  t.function = func
  return t
end

Coroutine.create returns a thread, not a table.

I'm not sure if this would solve your problem, but you could use coroutine.wrap() instead of coroutine.create(), which returns a function that works the same as a coroutine, and "coroutine.resume(co)" would be "co()" using a wrapped coroutine.