parse array error

[vislee]

local s = [[# test
ssl:
  certs:
  - |-
    -----BEGIN CERTIFICATE-----
    111111
    -----END CERTIFICATE-----
  - |-
    -----BEGIN CERTIFICATE-----
    222222
    -----END CERTIFICATE-----
]]


local yaml  = require("./tinyyaml")
local x = yaml.parse(s)
print(x["ssl"]["certs"][1])

luajit ./t.lua
luajit: .///tinyyaml.lua:310: attempt to compare number with nil
stack traceback:
	.///tinyyaml.lua:310: in function 'parsescalar'
	.///tinyyaml.lua:548: in function 'parseseq'
	.///tinyyaml.lua:680: in function 'parsemap'
	.///tinyyaml.lua:690: in function 'parsemap'
	.///tinyyaml.lua:740: in function 'parsedocuments'
	.///tinyyaml.lua:765: in function 'parse'