Romeu Moura

Romeu Moura

Systemics of the Liskov Substitution Principle

@malk_zameth · France



Endless conversation — with friends & compilers — on art, crafts, dialectic, paradigm jump, serendipity.


The Systemics of the Liskov Substitution Principle

The Liskov Substitution Principle: the least known and most frequently violated of all S.O.L.I.D.!

Let’s explore together what it is, why you should care, how to detect violations, how to stop violating, what is co-variance and contra-variance (What is the In/Out of C#, the Super/Extends of Java, the +/- of Scala).

But above all: Let’s see that the essence of Liskov is the essence of Object Orientation itself: Systemics

Let’s learn to see our codebase as a System.


Property-Based Tests

Property based testing is probably the tool with the biggest impact for so little investment you could have in your arsenal: at least when talking about tests.

It will give you fewer tests that will test much more and document the domain a lot better. It will also give you many hints about your design process.

All that while needing a very modest personal investment and being useable on legacy codebases very quickly.

The goal of this hands-on is for you to start doing that and be ready to add this tool to your bag on your day to day job.

You’ll need a laptop with your dev environment of choice and if possible a PBT framework already installed for your language (just google "language name" and QuickCheck)

The Premier Software Modelling & Design Conference

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Amsterdam, Jan 30 – Feb 2, 2018



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