Examples of different types of decorators

decorators.js

export function ClassDecorator(meta?: any): Function {
    return function (target: any) {
        let targetProto = target.prototype;
        let targetMeta = targetProto.__meta = targetProto.__meta || {};
        targetMeta.cls = meta;
    };
}

export function MethodDecorator(meta?: any): Function {
    return function (targetProto: any, methodName: string) {
        let targetMeta = targetProto.__meta = targetProto.__meta || {};
        targetMeta.methods = targetMeta.methods || {};
        targetMeta.methods[methodName] = meta;
    };
}

export function PropertyDecorator(meta?: any): Function {
    return function (targetProto: any, propertyName: string) {
        let targetMeta = targetProto.__meta = targetProto.__meta || {};
        targetMeta.properties = targetMeta.properties || {};
        targetMeta.properties[propertyName] = meta;
    };
}