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ocamlsyntax-errorshebang

OCaml shebang syntax error

$ cat hello.ml 
#!/usr/bin/env ocamlrun ocaml

let rec main = print_string "Hello World!\n"

$ ./hello.ml 
Hello World!

$ ocaml hello.ml 
Hello World!

$ ocamlc -o hello hello.ml 
File "hello.ml", line 1, characters 0-1:
Error: Syntax error

$ ocamlopt -o hello hello.ml 
File "hello.ml", line 1, characters 0-1:
Error: Syntax error

Similar to Erlang, OCaml permits shebangs in scripted mode, but borks in compiled mode. Is there a more idiomatic shebang in OCaml, one that doesn't trigger a syntax error during compilation?

Solution

  • Just use sed as a preprocessor. To remove the shebang on the first line, if found, pass:

    -pp 'sed "1 s/^#\!.*$//"'

    to ocamlc or ocamlopt.