Cómo imprimir tipos de datos en dardo

int integerValue = 2;
double doubleValue = 3.337;
var operationResult = integerValue * doubleValue; // operationResult is of
// double datatype.

print('$operationResult, type: ' + operationResult.runtimeType.toString());  // prints "6.674, type: double"
print(operationResult.runtimeType);  // prints "double"
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