Why does ReSharper's "Rename" only sometimes display a prompt?

When I rename a variable using ReSharper 4.5 (VS2开发者_Go百科008), the rename is performed inline (I specify the new variable name in the editor itself) or via a prompt (a popup window where I specify the new variable name).

I'm hoping someone can tell me what determines which approach is used?

I believe it lets you edit it inline depending on the variables scope. If it is local, it only needs to refactor the current methods reference to the variable.

Otherwise it needs to refactor all references to the variable or a method that occur in other files. The prompt lets you specify if you want to look in comments and if you want to open all the affected files, since the change may affect multiple files.