Comment by balnaphone

It works fine with GNU env with -S support, and a GNU-compatible kernel. I'm aware that won't work on some other systems, hence the 9 other examples. I said I would try that first and see how it goes, and low and behold it works fine on the systems I use.

  $ cat bbb.ml 
  #!/usr/bin/env -S "/home/user/.local/bin/o c a m l" -no-version
  print_endline "ok";;
  $ ls -lh ~/.local/bin/"o c a m l"
  lrwxrwxrwx 1 user user 14 Feb 27 07:26 '/home/user/.local/bin/o c a m l' -> /usr/bin/ocaml
  $ chmod a+rx bbb.ml
  $ ./bbb.ml
  ok
  $ 

But if it didn't work, you can get pretty good mileage out of abusing sh to get the job done for many popular languages.