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flutter - Sort List by alphabetical order

I'm trying to sort a list by alphabetical order and tried porting something i had in javascript to flutter. But it gives me an exception on String that it does not have the instance method '<'. I hope someone can help me fix this. Because i have no clue how to correct this issue.

data.sort((a, b) {
            var aName = a['name'].toLowerCase();
            var bName = b['name'].toLowerCase();
            return ((aName < bName) ? -1 : ((aName > bName) ? 1 : 0));
        });

I get this exception:

E/flutter (16823): [ERROR:topaz/lib/tonic/logging/dart_error.cc(16)] Unhandled exception:
E/flutter (16823): NoSuchMethodError: Class 'String' has no instance method '<'.
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by (71.8m points)

< and > is usually a shortcut to a compareTo method.

just use that method instead.

data.sort((a, b) {
  return a['name'].toLowerCase().compareTo(b['name'].toLowerCase());
});

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