Hi there. I created the project from the tutorial Quickstart an OCaml app project using Dune dune init project dummy and edited the lib/dune and lib/lib.ml files to look like this (* lib/dune *) (library (name lib)) (* lib/lib.ml *) let add x y = x + y let sub x y = x - y When running the c…

As a followup to the other good advice you’ve received, correcting your syntax error should sort you out: open Dummy let () = let result = Lib.add 7 0 in print_endline(string_of_int result); let result = Lib.sub 72 1 in print_endline (string_of_int result)

The single ; is used to separate expressions (like print_int 5). open Module is not an expression but a statement.

It worked like a charm. But I don’t understand why do I need to use let () =. I was poking around the docs and samples and it seemed to me that there is not a main function to work as an entry point in Ocaml (like the main() in C, for instance). I’m also aware that let () = is used as an entry p…

[image] plicatibu: It worked without the let () =. It probably just happened to work because you only had one expression in the entire file. Always use the let () = ... at the top level of a module for each expression that is not defining an identifier for later use, but is only for side effe…

The correct ways to test a file from the lib folder

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yawaramin August 4, 2023, 4:37am 2

See Syntax Error on "in" - #5 by yawaramin

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The correct ways to test a file from the lib folder

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