Domain modelling in object-oriented and functional programming, based on C# and F#

on YouTube ↗37m

" summary

Argues that domain modelling works better when code mirrors domain and incorrect states are unrepresentable, comparing C# and F# examples. Shows concrete models: policies, vehicles, movable black boxes, and engines, implemented with discriminated unions and records in F# versus classes and inheritance in C#. Demonstrates validation in constructors, the alternative of returning an error union instead of throwing, a function type for behavior (vehicle * distance -> vehicle), and how F# keeps many simple types in one file via type inference.

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" chapters (10)

1. 0:00Introduction and context
2. 2:54Classical domain modeling
3. 5:58Domain modeling limitations
4. 9:34Principles of modeling
5. 12:29OOP modeling implementation
6. 15:45Functional programming basics
7. 19:07FP modeling implementation
8. 22:53Complex modeling scenarios
9. 26:15Functional modeling details
10. 29:47Final thoughts and Q&A

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