Parameter hints show the names of function parameters for the passed arguments. CLion displays them in the editor inlined with your code to improve its readability:
Hints require the Clangd-based engine to be turned on (enabled by default).
Parameter hints are displayed for argument literals and expressions with more than one operand: function calls, lambdas, initializer lists, macro expressions, and constructors (including the constructors invoked through emplace_back-like functions). Hints for initializers are not shown when the argument is used as a designated initializer.
Arguments passed by non-const reference show the hint
&: to indicate the fact they can be modified:
Hide parameter hints
The hints are enabled by default. To hide them, go to Show parameter names hints checkbox.and clear the
Configure the parameter hints exception list
To hide parameter hints for particular cases, configure the list of exceptions.
Go to Configure next to the Show parameter names hints checkbox.and click
Make sure C/C++ is selected in the Language list.
Add methods for which you don't want to see the hints to the Blacklist section.
Enable additional options at the bottom of the dialog if required.
You can also adjust the hints settings right from the editor:
Press Alt+Enter on a hint to quickly disable it for the current function.
Right-click a hint and select from the list of options.