Permissions issue when running dune build

[porcupinenick]

I'm having some trouble running through this tutorial: https://github.com/janestreet/install-ocaml

I've cloned the files, installed the dependencies, but I'm not able to run 'dune' properly.

I'm running this command within the 01-install-ocaml folder: dune build hello_world.exe
I get this: -bash: ./dune: Permission denied

Then, I run using this command: sudo dune build hello_world.exe
I get this: sudo: dune: command not found

Here's my environment setup: macOS 10.15.2 (Catalina) and 'bash' in Terminal. Are there any steps I've missed? How would I check?

[xclerc]

One thing that comes to mind is that you may have . in your path.
That would explain the "permission denied" (trying to execute the
01-hello-world/dune file).

[porcupinenick]

did I mistakenly miss a step in the initial setup process?

[haohangxu]

Can you try running this?

opam install dune

[porcupinenick]

[NOTE] Package dune is already installed (current version is 2.0.0).

[xclerc]

Actually I am not sure what I said before really makes sense,
but I would try to execute the following:

which dune

[porcupinenick]

that's weird.....it doesn't give me the path.

[xclerc]

Could you try echo $PATH?

[porcupinenick]

is there a specific directory you would like me to run it in?

[xclerc]

No specific directory, but be sure to execute it from
a terminal exhibiting the problem.

[porcupinenick]

is there anything I should be expecting?

[porcupinenick]

I'm not seeing anything related to OPAM/dune in the output.

[xclerc]

I expect the variable (whose components are :-separated),
to contain .. It would mean that instead of trying to execute
the dune binary, your shell tries to execute this file, which is
not executable.

[porcupinenick]

I do see the '.'

[porcupinenick]

Have I just downloaded the incorrect project directory? Also, why am I not seeing the hello_world.exe file in the 01-hello-world folder for the install-ocaml repo?

[haohangxu]

I suspect this is not a problem with the source code here, likely a weird environment/misconfiguration problem as xclerc suggests.

hello_world.exe is the executable compiled hello_world.ml. dune is the compiler, so given that you're having trouble getting dune to work, it's expected that you won't see hello_world.exe.

Can you try this?

eval $(opam env)
which dune

[porcupinenick]

Ok, that worked!

[porcupinenick]

But another question:

git clone https://github.com/janestreet/install-ocaml
cd install-ocaml/01-hello-world

^ after following those instructions, I still don't see hello_world.exe; I haven't generated anything. How did you know to build the program like this:

dune build hello_world.exe
dune exec ./hello_world.exe

[haohangxu]

Those build instructions are outlined in the readme:
https://github.com/janestreet/install-ocaml#test-that-you-can-build-basic-program

[porcupinenick]

Ok, thanks. I referenced this link for more info:

https://dune.readthedocs.io/en/latest/quick-start.html

It seems that within the project folder, there is a dune file. That dune file specifies the name of the executable (hello_world.exe in this case) which is built by dune.

1. May I submit a PR to this link within the description for more background information on where the .exe is coming from?

2. Once I start-up a new .bash shell and run 'which dune', I don't see the file path. Once I run these two commands (eval $(opam env); which dune), I see the path. Perhaps I can also submit a PR regarding solving this issue for more context?