score:1

Accepted answer

this is obviously a bug in the example. maybe the library was changed and the example not yet tested with the new version.

if you add two values to the map it works though

 bool chartbool = new bool({
      'labels' : ["montag","dienstag","mittwoch","donnerstag","freitag","samstag","sonntag"],
      'datasets' : [
                  {
                    'name': 'bla',
                    'date': 'somedate',
                    'strokecolor' : "rgba(255,10,10,1)",

i just added the two lines name': 'bla','date': 'somedate'. it looks these values are just used as tooltip and the content doesn't really matter to overcome the exception.