Type-Specific Identifiers

This lesson will teach us how to explicitly set the type of our let binding.

We'll cover the following

As we’ve seen so far, keeping track of the type of data we have is very important. Languages like JavaScript or Python do not require that we mention the explicit type of a variable.

In other languages like C++ or Java, we have to specify the type of a variable when declaring it.

Reason has the best of both worlds! In the previous lesson, we saw how let bindings could automatically detect the data type of a value. However, if needed, we can explicitly specify the data type which our let binding should have.

Type Annotations

The type of binding can be annotated next to the name of the identifier, preceded by the : keyword:

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