UE4 introduced the ability to use function inputs as variables (“Function inputs are now exposed as variable “Get” nodes via the right-click context menu in a Blueprint function graph context.”).
Unfortunately, when you change the input’s name type, all existing references inside the function will keep the original name and thus result in the compiler error:
“Error The property associated with could not be found”
Similarly a change of the input type also won’t affect references.
Screenshot: http://imgur.com/a/HYyYM
Steps to reproduce:
Inside a bp actor create function named "test function".
Add input of type integer named "test input".
Add output of type integer named "test output".
Right click in the graph and type "get test input" to create a reference.
Plug the pin of the "Get test input" node into "test output".
Select function node and in details rename "test input" to "test input 2".
Compile.
Current result: the node “Get test input” keeps it’s name, compilation results in the error “Error The property associated with test input could not be found” and a warning: “Warning Unable to find local variable with name ‘test input’ for Get test input”
Expected result: upon changing the function input’s name or type (step 6) all previously created references / Get nodes (step 4) should receive the new name and / or new type, the same way it happens with local variables.