Explore creating robust HTTP services in Scala's functional programming paradigm. Gain insights into pure vs. impure implementations, their pros and cons, and effective tool usage.

scala-platform.tar.gz

Scala-Pure

Scala-Impure

Scala-Tapir

Scala-Impure-Test

Scala-Pure-Test

Scala-Tapir-Test

Test

Scala - Run Code Widget 

Scala-Pure-copy

Scala is one of the most popular general-purpose languages that supports both object-oriented and functional programming. In this course, you will learn how to create back-end HTTP services using Scala's functional programming paradigm.

You will also learn how to develop, test, and document the service using both pure and impure ways. You will be exposed to the differences between pure and impure implementation, their respective pros and cons, and how pure implementation can be more robust in terms of performance, understandability, testability, and type safeness. 

By the end of the course, you will have a clear idea of how functional programming works in Scala and how you can use the available tools more effectively.

Pure Functional HTTP APIs in Scala

It relies on the simplest version of code.

It makes our code easier to reason about.

Why is referential transparency important?

Why is referential transparency important?

Suppose we have a program with an expression `e` in it. When we evaluate the expression `e`, we get `g`. 

In the original version of the program, we get `A` as our output. But when we decide to replace `e` with `g` everywhere in our code, we get the output `B`.

Is the code referentially transparent?

Suppose we have a program with an expression <code>e</code> in it. When we evaluate the expression <code>e</code>, we get <code>g</code>.
In the original version of the program, we get <code>A</code> as our output. But when we decide to replace <code>e</code> with <code>g</code> everywhere in our code, we get the output <code>B</code>.
Is the code referentially transparent?

```
1 val num = 3 + 2
2 println("My number is: ")
3 println(num)
```

If the code above followed lazy evaluation, on which line would the expression `3+2` be evaluated?

<pre><code>1 val num = 3 + 2
2 println(&quot;My number is: &quot;)
3 println(num)
</code></pre>
If the code above followed lazy evaluation, on which line would the expression <code>3+2</code> be evaluated?

Test your knowledge and understanding by taking a quiz on functional programming in Scala.

Introduction

Impure Implementation

Pure Implementation

Testing Impure Services

Testing Pure Services

Benchmarks

Documentation

Epilogue

Quiz on Functional Programming in Scala