attempt to call Global 'getaltar' (a nil value) error

Dear Sir,

Below is my script & Error,.. please Guide me



-- patterns



altar = Pattern("altar.png")



-- functions



function move_map(where)



where = where or math.randomseed(os.time())



local move = {

{

-- down

Location(350, 700),

Location(350, 150),

},

{

-- up

Location(350, 150),

Location(350, 700),

},

{

--left

Location(60, 560),

Location(560, 560),

},

{

--right

Location(560, 560),

Location(60, 560),

},

}



-- pick a random move

local move_to = math.random(1, #move)

toast(move_to)

swipe(move[move_to][1], move[move_to][2])

wait(3)



end





function search_map(num_try)





-- vars

num_try = 3

local timer_local = Timer()



-- for each try

for i = 1, num_try do

if exists(altar) then

toast(tostring(altar) .. " found after: " .. timer_local:check())



-- this will breack the infinite loop

return getLastMatch()

end





-- max try will return false

return false

end



local getaltar = function()



while true do



wait(3)



if altar then



toast("altarFound after: " .. t:check())

getLastMatch():highlight(3)

wait(1)

click(getLastMatch())

wait(2)

click(Location(215,910))

wait(2)

click(Location(530,1185))

wait(2)

click(Location(375,1185))

wait(2)

search_map()

else

move_map()

end

end

end

end



getaltar() -- error here



attempt to call global 'getaltar(a nil value)
stack traceback: