Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!
You can use the shortcut ctrl + shift + p to show inferred type of a variable
when the cursor is on the variable in IntelliJ IDEA.
You can also configure IntelliJ to show Scala data types
when you hover over a variable.
File > Other Settings > Default Settings ...
Go to “Languages & Frameworks” > Scala
Go to the Editor tab
Enable “Show type info on mouse hover after X ms”
Apply/save changes.