Difference between files beginning with upper or lower case

What is the difference between files beginning with upper and lower case?

For example, in the Menhir source – https://gitlab.inria.fr/fpottier/menhir/tree/master/src – some files begin with upper case and some with lower case.

OCaml maps file names to modules:

  • abc.ml becomes module Abc
  • Abc.ml becomes module Abc
  • aBC.ml becomes module ABC
  • ABC.ml becomes module ABC

Capitalising the first letter in the file name has no effect since a module name is always capitalised. See module_of_filename in the compiler source code.