Type inference improvements

There have been several type inference improvements in modern Java. To be able to support lambdas, the way the compiler infers things has been improved to use target typing extensively. This and other improvements over Java 7's inference were managed under the Open JDK Enhancement Proposal (JEP) 101.

Before we get into those, lets recap on the basics.

Type inference refers to the ability for a programming language to automatically deduce the type of an expression.

Statically typed languages know the types of things at compile time. Dynamically typed languages know the types at runtime. A statically typed language can use type inference and drop type information in source code and use the compiler to figure out what's missing.

So this means that type inference can be used by statically typed languages (like Scala) to "look" like dynamic languages (like JavaScript). At least at the source code level.

Here's an example of a line of code in Scala:

val name = "Henry"

You...