Thanks for your answers.
Unfortunately, I still have this error and a new one 
By upgrading the rescript-classnames module, the installed version of @rescript/core is 1.3.0
As I seen in the README, this version is only compatible with uncurried projects and mine is not, so I tried to force the resolution of the package to the 1.2.0 & 1.1.0 version but without success 