tests/cases/conformance/expressions/assignmentOperator/compoundAdditionAssignmentLHSCanBeAssigned.ts(32,1): error TS2365: Operator '+=' cannot be applied to types 'number' and 'null'.
tests/cases/conformance/expressions/assignmentOperator/compoundAdditionAssignmentLHSCanBeAssigned.ts(33,1): error TS2365: Operator '+=' cannot be applied to types 'number' and 'undefined'.
tests/cases/conformance/expressions/assignmentOperator/compoundAdditionAssignmentLHSCanBeAssigned.ts(39,1): error TS2365: Operator '+=' cannot be applied to types 'E' and 'null'.
tests/cases/conformance/expressions/assignmentOperator/compoundAdditionAssignmentLHSCanBeAssigned.ts(40,1): error TS2365: Operator '+=' cannot be applied to types 'E' and 'undefined'.


==== tests/cases/conformance/expressions/assignmentOperator/compoundAdditionAssignmentLHSCanBeAssigned.ts (4 errors) ====
    enum E { a, b }
    
    var a: any;
    var b: void;
    
    var x1: any;
    x1 += a;
    x1 += b;
    x1 += true;
    x1 += 0;
    x1 += '';
    x1 += E.a;
    x1 += {};
    x1 += null;
    x1 += undefined;
    
    var x2: string;
    x2 += a;
    x2 += b;
    x2 += true;
    x2 += 0;
    x2 += '';
    x2 += E.a;
    x2 += {};
    x2 += null;
    x2 += undefined;
    
    var x3: number;
    x3 += a;
    x3 += 0;
    x3 += E.a;
    x3 += null;
    ~~~~~~~~~~
!!! error TS2365: Operator '+=' cannot be applied to types 'number' and 'null'.
    x3 += undefined;
    ~~~~~~~~~~~~~~~
!!! error TS2365: Operator '+=' cannot be applied to types 'number' and 'undefined'.
    
    var x4: E;
    x4 += a;
    x4 += 0;
    x4 += E.a;
    x4 += null;
    ~~~~~~~~~~
!!! error TS2365: Operator '+=' cannot be applied to types 'E' and 'null'.
    x4 += undefined;
    ~~~~~~~~~~~~~~~
!!! error TS2365: Operator '+=' cannot be applied to types 'E' and 'undefined'.
    
    var x5: boolean;
    x5 += a;
    
    var x6: {};
    x6 += a;
    x6 += '';
    
    var x7: void;
    x7 += a;