Two Useful Methods of IEnumerable

I found myself writing this piece of code:

var allTexts = new List<Text>();

Here I needed to create a new list containing another list and add one element to the beginning and to the end.

If it were JS, I would write something like this:

const allTexts = [introText, ...texts, conclusionText];

It utilizes destructuring to embed texts in the middle of the new array. It is a cleaner way to do it in a functional style.

C# doesn't support array destructuring. One way to rewrite the C# code above is this:

var allTexts = (new Text[] { introText }).Concat(texts).Concat((new Text[] { conclusionText }));

This is even uglier than before. Fortunately, now C# has Prepend and Append methods out of the box:

var allTexts = texts.Prepend(introText).Append(conclusionText);

Note: Prepend and Append methods do not modify the elements of the collection. Instead, they create a copy of the collection with the new element.