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Demeter’s Law: Don’t talk to strangers!

Carlos Caballero on March 08, 2019

The Law of Demeter (LoD) or principle of least knowledge is a design guideline for developing software, particularly object-oriented programs — ...

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MarioTK • Oct 23 '19 • Edited

Dear Dr.Caballero,

I'm sorry to disturb you. I'm a computer science student

Demeter's law should simplify the dependency graph, reducing the overall coupling. The objective of this law is to improve encapsulation.

An object of class B (status information of A) should not return to A an object of class C (status information of B).

Right?

Thank you

Dávid Horváth • Sep 29 '19

But "person.isZipCode(zipCode)" is (reverse) coupled to the consumer, isn't it? Even worse, we must also change House for getting zipcode or any other "random" information, such as "person.isLivingInCircle(geoCoords, maxDist)" or "person.isZipCodePrime()".