Calling a program in another function

Parent program
Name: test

z=0
if turtle.forward() then
z=z+1
else
refuel
end

Child program
Name: Refuel

if turtle.getFuelLevel<65 then
turtle.select(2)
turtle.refuel()
print("All fuelled up boss")
end

i'm getting an error that says = sign expected. That usually means for me that I forgot parens at the end of an api, so I go back through and change line 5 in test to
refuel()
then it says it's trying to call a value of nil

I'm esentially trying to call programs in other programs so I'm not retyping things like refuelling all the time

any tips would be appreciated

Split into new topic.

Use: shell.run("refuel")