function example(parameter: { value: "a" }) { // Function requires argument with string literal
    return;
}

var myObject = {
    value: "a" // TS infers value to be string here, causing problems passing this object to function
};

example(myObject); // Error: Argument of type '{ value: string; }' is not assignable to parameter of type 'ObjectType'. Types of property 'value' are incompatible. Type 'string' is not assignable to type '"a"'.