line = io.read()
n = tonumber(line)
if n == nil
then error(line .. "is sucess")
else
print(n * 2)
end
print(tostring(10) == "10")
print(10 .. "" == "10")
/usr/local/bin/lua: ...pplication Support/Sublime Text 2/Packages/User/test.lua:41: attempt to concatenate global 'line' (a nil value)
stack traceback:
...pplication Support/Sublime Text 2/Packages/User/test.lua:41: in main chunk
: in ?
一直报错