Loading collection data...
Collections are a way for you to organize kata so that you can create your own training routines. Every collection you create is public and automatically sharable with other warriors. After you have added a few kata to a collection you and others can train on the kata contained within the collection.
Get started now by creating a new collection.
Can you explain, please, what does "|" mean in this solution?
This comment is hidden because it contains spoiler information about the solution
TypeError: Cannot read property 'caller' of null
at /runner/frameworks/javascript/cw-2.js:159:11
at Promise._execute
at Promise._resolveFromExecutor
at new Promise
at Object.describe
at Object.handleError
at ContextifyScript.Script.runInThisContext
at Object.exports.runInThisContext