clazz("Person", {
    constants: {
        SEX: ['male', 'female']
    },
    properties: {
        name: {
            type: 'string',
            methods: ['get']
        },
        phone: {
            type: ['string', {
                pattern: /\d{1,2}-\d{3}-\d{5,7}/
            }]
        },
        birthday: {
            type: 'datetime',
            constratins: {
                inPast: function(birthday) {
                    return birthday.getTime() < Date.now();
                }
            }
        },
        sex: {
            type: 'string',
            methods: ['get', 'set', 'is'],
            converters: {
                toFull: function(sex) {
                    switch(sex.toLowerCase()) {
                        case 'm': sex = 'male'; break;
                        case 'f': sex = 'female'; break;
                    }
                    return sex;
                }
            },
            constraints: {
                existedSex: function(sex) {
                    return -1 !== this.const('SEX').indexOf(sex);
                }
            }
        }
    },
    methods: {
        getAge: function() {
            return (new Date()).getFullYear() - this.getBirthday().getFullYear();
        }
    }
});

clazz('Teacher', 'Person', {
    constants: {
        SUBJECT: ['physics', 'literature', 'mathematics']
    },
    properties: {
        subject: {
            type: 'string',
            constraints: {
                existedSubject: function(subject) {
                    return -1 !== this.const('SUBJECT').indexOf(subject);
                }
            }
        }
    }
});

 
// Create just common person - John (without 'new' operator)
var john = clazz('Person').create({
    name: 'John Stewart',
    sex: 'M',
    phone: '1-925-123567',
    birthday: "1989-12-13"
});
 
john instanceof clazz("Person"); // true 
 
john.getName();  // 'John Stewart'
john.getAge();   // 24
john.getSex();   // 'male'
john.getPhone(); // 1-925-123567
 
john.setPhone('7-925-1'); // Throw phone pattern fail error with message: 
                          // 'Value "7-925-1" does not match
                          // pattern "/\d{1,2}-\d{3}-\d{5,7}/"'
 
john.isSex("male");   // true
john.isSex("female"); // false
 
john.setSex('unsupportedSex'); // Throw existedSex constraint fail error with message:
                               // 'Constraint "existedSex" was failed!'
 
john.setSex('female'); // Successfully change sex of John
 
john.getSex();        // 'female'
john.isSex("male");   // false
john.isSex("female"); // true
 
john.getBirthday() instanceof Date; // true
john.getBirthday().getMonth();      // 12
john.getBirthday().getFullYear();   // 1989
 
// Create math teacher - Mr. George Smith. (with 'new' operator)
var mathTeacher = new clazz('Teacher')({
    name: 'George Smith',
    sex: 'male',
    birthday: '1973-12-34',
    subject: 'mathematics'
});
 
mathTeacher instanceof clazz('Person');    // true
mathTeacher instanceof clazz('Teacher'));  // true
 
mathTeacher.getName(); // John Smith