var numOrDate: number | Date;
var strOrBoolean: string | boolean;
var strOrNum: string | number;

// If each type in U has construct signatures and the sets of construct signatures are identical ignoring return types, 
// U has the same set of construct signatures, but with return types that are unions of the return types of the respective construct signatures from each type in U.
var unionOfDifferentReturnType: { new (a: number): number; } | { new (a: number): Date; };
numOrDate = new unionOfDifferentReturnType(10);
strOrBoolean = new unionOfDifferentReturnType("hello"); // error 
new unionOfDifferentReturnType1(true); // error in type of parameter

var unionOfDifferentReturnType1: { new (a: number): number; new (a: string): string; } | { new (a: number): Date; new (a: string): boolean; };
numOrDate = new unionOfDifferentReturnType1(10);
strOrBoolean = new unionOfDifferentReturnType1("hello");
new unionOfDifferentReturnType1(true); // error in type of parameter
new unionOfDifferentReturnType1(); // error missing parameter

var unionOfDifferentParameterTypes: { new (a: number): number; } | { new (a: string): Date; };
new unionOfDifferentParameterTypes(10);// error - no call signatures
new unionOfDifferentParameterTypes("hello");// error - no call signatures
new unionOfDifferentParameterTypes();// error - no call signatures

var unionOfDifferentNumberOfSignatures: { new (a: number): number; } | { new (a: number): Date; new (a: string): boolean; };
new unionOfDifferentNumberOfSignatures(); // error - no call signatures
new unionOfDifferentNumberOfSignatures(10); // error - no call signatures
new unionOfDifferentNumberOfSignatures("hello"); // error - no call signatures

var unionWithDifferentParameterCount: { new (a: string): string; } | { new (a: string, b: number): number; };
new unionWithDifferentParameterCount();// no  call signature
new unionWithDifferentParameterCount("hello");// no  call signature
new unionWithDifferentParameterCount("hello", 10);// no  call signature

var unionWithOptionalParameter1: { new (a: string, b?: number): string; } | { new (a: string, b?: number): number; };
strOrNum = new unionWithOptionalParameter1('hello');
strOrNum = new unionWithOptionalParameter1('hello', 10);
strOrNum = new unionWithOptionalParameter1('hello', "hello"); // error in parameter type
strOrNum = new unionWithOptionalParameter1(); // error

var unionWithOptionalParameter2: { new (a: string, b?: number): string; } | { new (a: string, b: number): number };
strOrNum = new unionWithOptionalParameter2('hello'); // error no call signature
strOrNum = new unionWithOptionalParameter2('hello', 10); // error no call signature
strOrNum = new unionWithOptionalParameter2('hello', "hello"); // error no call signature
strOrNum = new unionWithOptionalParameter2(); // error no call signature

var unionWithOptionalParameter3: { new (a: string, b?: number): string; } | { new (a: string): number; };
strOrNum = new unionWithOptionalParameter3('hello'); // error no call signature
strOrNum = new unionWithOptionalParameter3('hello', 10); // error no call signature
strOrNum = new unionWithOptionalParameter3('hello', "hello"); // error no call signature
strOrNum = new unionWithOptionalParameter3(); // error no call signature

var unionWithRestParameter1: { new (a: string, ...b: number[]): string; } | { new (a: string, ...b: number[]): number };
strOrNum = new unionWithRestParameter1('hello');
strOrNum = new unionWithRestParameter1('hello', 10);
strOrNum = new unionWithRestParameter1('hello', 10, 11);
strOrNum = new unionWithRestParameter1('hello', "hello"); // error in parameter type
strOrNum = new unionWithRestParameter1(); // error

var unionWithRestParameter2: { new (a: string, ...b: number[]): string; } | { new (a: string, b: number): number };
strOrNum = new unionWithRestParameter2('hello'); // error no call signature
strOrNum = new unionWithRestParameter2('hello', 10); // error no call signature
strOrNum = new unionWithRestParameter2('hello', 10, 11); // error no call signature
strOrNum = new unionWithRestParameter2('hello', "hello"); // error no call signature
strOrNum = new unionWithRestParameter2(); // error no call signature

var unionWithRestParameter3: { new (a: string, ...b: number[]): string; } | { new (a: string): number };
strOrNum = new unionWithRestParameter3('hello'); // error no call signature
strOrNum = new unionWithRestParameter3('hello', 10); // error no call signature
strOrNum = new unionWithRestParameter3('hello', 10, 11); // error no call signature
strOrNum = new unionWithRestParameter3('hello', "hello"); // error no call signature
strOrNum = new unionWithRestParameter3(); // error no call signature
