# Presentation

## Slides

This git-book is here to supplement training sessions I've conducted using slides located in this repository:

{% embed url="<https://github.com/rdeneau/formation-fsharp/tree/main/en>" %}

* Written in markdown with marp / marpit
* Outputs available in HTML and PDF files
* The theme can be customized: it's "just" CSS and PNG files.

## Author

Romain DENEAU

* Senior Developer F♯ C♯ TypeScript
* Github [/rdeneau](https://github.com/rdeneau)
* Linked-in [romain-deneau](https://www.linkedin.com/in/romain-deneau-95481143/)
* ~~Twitter/X~~ [~~@DeneauRomain~~](https://x.com/DeneauRomain)

## Why F♯

[Answer in a single tweet](https://nitter.net/MokoSharma/status/1458151277343379457) :

<figure><img src="/files/k8EYZHbkmHxDgECObXyg" alt=""><figcaption></figcaption></figure>

In detail :

* Multi-paradigm language with a strong functional orientation
  * Functional programming *(FP)* principles: immutability and composition
  * Building blocks: functions and algebraic data types *(ADT)*
* "Fun" ! Very pleasant to write and read
  * Expressive and concise (not very verbose syntax)
  * Sensitive to indentation → easy to read
  * Strong static typing but it's almost seamless thanks to type inference
* Language entreprise-friendly
  * Runs on the .NET platform → high performance, easy interop with C# projects, .NET ecosystem and libraries
  * Very good tooling: Visual Studio, VsCode, Rider
  * Robust code: predictable and reproducible results (immutability, structural equality, no nulls, exhaustive pattern matching)
  * Interactive programming: check code by evaluating it in the FSI console
  * Narrowed community but strong and friendly
* F♯ compared to other back-end functional languages
  * Its syntax is not hybrid, unlike **Scala** and **Kotlin** (mixing OOP and FP)
  * Easier to learn than **Haskell** or **OCaml** *(but with fewer FP features, partially compensated for by OOP features)*
  * Static typing, unlike **Closure** *(and far fewer brackets 😜)*

## Convention

📍 → concept addressed later, generally with the associated link

💥 → compilation error or runtime exception

🚀 → more advanced chapters

🍔 or 🎲 → Quiz

📜 → Summary

## Target audience

C# Developers - .NET SDK installed on your machine\
Notions in JavaScript/TypeScript can be helpful when we compare the languages

{% hint style="success" %}

#### Perform the training yourself

As a F# developer in a .NET team using only C#, feel free to use these materials (both git-book and slides) to train your team.

💡 The theme can be customized: it's "just" CSS and PNG files.
{% endhint %}

## Changelog

### 2025-08-21

* Improve [Functional patterns](/fsharp-training/monadic-types/4-functional-pattern.md)
* Improve [Computation expression (CE)](/fsharp-training/monadic-types/5-computation-expressions.md)
* Fix a lot of typos (with the help of Copilot)

### 2025-05-13

* Dedicated page to cover everything regarding [Exceptions](/fsharp-training/fundamentals/2-syntax/exceptions.md)
* Misc. precisions regarding [Asynchronous programming](/fsharp-training/asynchronous-programming/1-async-workflow.md)

### 2025-04-02

* Translation from [French](https://rdeneau.gitbook.io/formation-fsharp-fr)


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