Why can't the var keyword in Java be assigned a lambda expression?

Question

It is allowed to assign var in Java 10 with a string like:

var foo = \"boo\";

While it is not allowed to assign it with a lambda e

Answer 1

Because that is a non-feature:

This treatment would be restricted to local variables with initializers, indexes in the enhanced for-loop, and locals declared in a traditional for-loop; it would not be available for method formals, constructor formals, method return types, fields, catch formals, or any other kind of variable declaration.

http://openjdk.java.net/jeps/286