IntelliJ IDEA 2017.2 Help

Working with Scala Show Type Info Action

The following is only valid when Scala Plugin is installed and enabled!

IntelliJ IDEA offers an easy way to work with type inference feature such as Scala Show Type Info action.

Entering code

  • Let's enter a random code and see what can be done:
    type info code

Invoking Show Type Info Action

  • If you select Show type info on mouse hover after, ms check box in Settings | Languages and Frameworks | Scala, then in the Editor, you can simply navigate with the mouse to a value to see its type information.
  • To invoke Show Type Info action in Editor, navigate to the value and press N/A:
    type info string
  • You can also see the type information on a value definition. Simply put the caret on a value definition and press N/A:
    type info int

Adding Type Annotation

  • To add a type annotation, highlight the value and press Alt+Enter:
    type info add
    As a result, the type annotation is added:
    type info add result
  • You can also use Adjust types action to shorten types with full qualified names.
    type adjust
    In this case the necessary imports are added.
    type adjust result

Removing Type Annotation

  • You can also remove the type annotation the same way you have added it, by pressing Alt+Enter:
    type info remove

Seeing Type Annotation on Expression

  • To see the type information on an expression, simply navigate to the expression, highlight it and press N/A:
    type info expression
Last modified: 29 November 2017