TypeError: days.split is not a function

[beatcode]

Das ausführen von generate.js führt zu folgendem Fehler. Ich hoffe ich parametrisiere richtig.

node generate.js -l "Todo, Doing, Done" -d "2017-01-01, 2017-01-12" -r "1,1" -f "Done" -t "10:00:00+01:00" -n "bi1-sprint" -d

/home/trello-burndown/generate.js:77
days = days.split(',');
^
TypeError: days.split is not a function
at Object. (/home/trello-burndown/generate.js:77:13)
at Module._compile (module.js:570:32)
at Object.Module._extensions..js (module.js:579:10)
at Module.load (module.js:487:32)
at tryModuleLoad (module.js:446:12)
at Function.Module._load (module.js:438:3)
at Module.runMain (module.js:604:10)
at run (bootstrap_node.js:394:7)
at startup (bootstrap_node.js:149:9)
at bootstrap_node.js:509:3