Thoughts about software development

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2021-06-21 05:00:05

Immutability is a special thing that in my mind deserves a short explanation and praise. If you're familiar with functional programming you surely recognice the concept of immutability because it's a key ingredient of the paradigm. In the world of object oriented programming it's not as used and as easy to use approach but there are ways to incorporate immutability to parts of the code and I strongly suggest you to do so.

We have a need to modify a object's property but because the object is immutable we can't just change value but instead we make a copy of the object and while making the copy we provide the new value for the copy. In code it looks something like this.

The same idea can be applied in functions and methods by thinking in terms of not changing the existing data. Functions have a input and a output. To achieve immutability you just have to make sure that what ever is your input it's never changed.

We want to increment a integer by one. Traditional mutating version is simply count++. Immutable version is a increment function that takes the current count as a input and as a output it should return the input + 1 without modifying the input object. The immutable function would look something like this.