Pragmatic Scala

Type Inference

Like any statically typed language, Scala verifies types of objects at compile time. At the same time, it does not require you to state the obvious; it can infer types. You can use type inference for both simple types and generics.

Type Inference for Simple Types

We’ll first explore type inference for simple types. Let’s start with a piece of code where we indicate the type, as we’re used to doing in languages like C++ and Java:

We defined a variable named greet, mentioned its type is String, and gave it a value. Unlike Java, where you specify the type and then the variable name, in Scala you do the reverse—for two reasons: First, by asking us to ...