reftex-string-to-label-function

reftex-string-to-label-function is a variable defined in `reftex-vars.el'.
Its value is

reftex-string-to-label

• This variable may be risky if used as a file-local variable.

Documentation:
Function to turn an arbitrary string into a valid label.
RefTeX's default function uses the variable `reftex-derive-label-parameters'.

You can customize this variable.