I try to compile an Ocaml project with an Ocaml version provided by Opam.
My ocamlbuild, ocamlfind, and oasis seem OK :
/Users/fred/.opam/4.02.1/bin/ocamlbuild
dhcp-182-73:compil fred$ which ocamlfind
/Users/fred/.opam/4.02.1/bin/ocamlfind
dhcp-182-73:compil fred$ which oasis
/Users/fred/.opam/4.02.1/bin/oasis
But when I try to compile, it seems that a wrong version of ocamlbuild is called, and even the version of ocamlfind is right, I think that it explains why ocamlfind can't find the sexplib library.
$ make
ocaml setup.ml -build
Finished, 0 targets (0 cached) in 00:00:00.
+ /Users/fred/.opam/system/bin/ocamlfind ocamldep -package threads -package sexplib.syntax -package core -package comparelib.syntax -modules src/tricot/tricot.mli > src/tricot/tricot.mli.depends
ocamlfind: Package `sexplib.syntax' not found
Command exited with code 2.
Compilation unsuccessful after building 1 target (0 cached) in 00:00:00.
E: Failure("Command ''/usr/local/bin/ocamlbuild' src/tricot/tricot.cma src/tricot/tricot.cmxa src/tricot/tricot.a src/tricot/tricot.cmxs src/compil/compil.cma src/compil/compil.cmxa src/compil/compil.a src/compil/compil.cmxs src/main.native -use-ocamlfind -tag debug' terminated with error code 10")
make: *** [build] Error 1
I've tried to tell oasis which version of ocambuild to use without success, does someone knows how it could be done ?
Thanks
Try deleting setup.data and running make again. Oasis caches the paths the first time you try to build, and doesn't update them automatically afterwards. Perhaps you tried to build it, then used opam switch, then tried to build it again?
You must be missing a
eval $(opam config env)
See the documentation of opam switch.
Note that normally opam's install procedure should have made so that this gets invoked automatically on new shells. You may want to run opam init again it will prompt you to agree to make changes to your .profile so that everything is in order when you start new shells.
EDIT: In fact it looks like you changed to the system switch between the two invocations you show us. So it seems that in the system switch sexp is not installed. In anycase whenever you opam switch in a shell always invoke the command I mentioned above so that the right paths are setup.
In addition to Thomas's answer, you can discard the configuration by
ocaml setup.ml -distclean
Related
I'm having trouble linking a very simple OCaml program:
open Core
Format.printf "hello world %s\n" "foobar";;
Format.printf "argv= %s\n" (Sys.get_argv()).(0) ;;
which I compile with
ocamlfind ocamlc -thread -package core visitor.ml
The compile step always generates the error:
Error: Required module `Core__Core_sys' is unavailable
I've pinned version 4.0.9, and I can see the file:
$ ocamlfind query core
/home/ubuntu/.opam/4.09.0/lib/core
and $ ls -la /home/ubuntu/.opam/4.09.0/lib/core shows
-rw-r--r-- 1 ubuntu ubuntu 17891 Dec 3 20:14 core__Core_sys.cmi
-rw-r--r-- 1 ubuntu ubuntu 93777 Dec 3 20:14 core__Core_sys.cmt
-rw-r--r-- 1 ubuntu ubuntu 75659 Dec 3 20:14 core__Core_sys.cmti
-rw-r--r-- 1 ubuntu ubuntu 16958 Dec 3 20:14 core__Core_sys.cmx
I've tried everything I can think of, with no luck. BTW, I notice that the documentation https://ocaml.org/api/Sys.html makes no mention at all of get_argv but if I try just plain Sys.argv I get a warning:
# Sys.argv ;;
Alert deprecated: Core.Sys.argv
[since 2019-08] Use [Sys.get_argv] instead, which has the correct behavior when [caml_sys_modify_argv] is called.
So I conclude that the core OCaml documentation published at ocaml.org is more than two years out of date! How can one obtain up-to-date documentation, ideally documentation that describes these kinds of newbie errors?
A few points. First, it looks like you are on a fairly old version of OCaml. Unless you need to stay on 4.09 for some reason, I highly recommend upgrading to the latest version, 4.13.1. Instructions for installing are here: https://ocaml.org/learn/tutorials/up_and_running.html
In case you have any trouble with that, try upgrading to the latest version of opam (the OCaml package manager) and doing opam update to download the most up-to-date package index.
Second, it looks like you are trying to use Jane Street's Core library, which is a third-party package which is intended as a standard library replacement. As such, it has its own version of the OCaml standard library's Sys module, i.e. Core.Sys. Regarding the alert that you are getting, the Core.Sys.argv value is actually deprecated by Jane Street Core: https://ocaml.janestreet.com/ocaml-core/latest/doc/core/Core__/Core_sys/index.html#val-argv
A single result from get_argv (). This value is indefinitely deprecated. It is kept for compatibility...
This leads us to the final issue, when you try to compile it is unable to find the core package. There are a couple of choices here. First, one option is that the core package and standard library replacement are actually optional; you may not actually need them. If you're an OCaml beginner you could try sticking with the standard library only (so no open Core, no trying to compile with the core package).
Another option, if you decide to keep using the core package, is to the dune build system instead of ocamlfind. Dune is a powerful, modern OCaml build system that handles almost all aspects of package linking during the build, so you don't need to worry about issuing individual compile commands.
Here's what a dune file would look like:
(executable
(name visitor)
(libraries core))
And the visitor.ml file would be in the same directory:
let () =
Printf.printf "hello world %s\n" "foobar";
Printf.printf "argv= %s\n" Sys.argv.(0)
Then you would run:
dune exec ./visitor.exe
The .exe is a dune convention, executables across operating systems are given this extension.
Finally, in source code you never actually need ;;. More about that here: https://discuss.ocaml.org/t/terminate-a-line-with-or-or-in-or-nothing/8941/21?u=yawaramin
Note on documentation being out of date: it would help if you could point us to where you got the instructions that led you to this point of confusion. There is a lot of effort to clean up install instructions and modernize documentation, but unfortunately there are a lot of outdated getting started guides out there. The 'Up and Running' link I provided at the top of this answer is the best resource.
You need to link the package by adding the -linkpkg flag:
ocamlfind ocamlc -thread -package core -linkpkg visitor.ml
I reviewed this thread OCaml - Cannot find graphics.cma but unfortunately wasn't able to resolve it finding the recommendation here. I'm on Catalina macos and when running ocamlbuild foo.byte, I get this error:
+ ocamlc.opt str.cma graphics.cma -thread threads.cma foo.cmo -o foo.byte
File "_none_", line 1:
Error: Cannot find file graphics.cma
Command exited with code 2.
Compilation unsuccessful after building 3 targets (0 cached) in 00:00:00.
I tried installing graphics via opam and installing xquartz as well manually after removing the brew version of xquartz which, enabled me to install graphics just fine but still gives me the error above.
Without more details, it sounds like you have not added the "graphics" package to your _tag file. (Detailing this dependency is also required with dune).
My problem is similar to this, however, in my case .ocamlinit is set.
Here is my ocaml version.
mymac:Desktop myusr$ ocaml --version
The OCaml toplevel, version 4.08.1
Here is my opam version.
mymac:Desktop myusr$ opam --version
2.0.5
Here is my opam switch.
mymac:Desktop myusr$ opam switch
# switch compiler description
→ 4.08.1 ocaml-base-compiler.4.08.1 4.08.1
default ocaml-base-compiler.4.08.1 default
Here's my .ocamlinit:
mymac:Desktop myusr$ cat ~/.ocamlinit
(* ## added by OPAM user-setup for ocamltop / base ## 3ec62baf6f9c219ae06d9814069da862 ## you can edit, but keep this line *)
#use "topfind";;
(* ## end of OPAM user-setup addition for ocamltop / base ## keep this line *)
#thread;;
#require "core.top";;
#require "core.syntax";;
Here is the evidence that I already have core installed.
mymac:Desktop myusr$ opam install core utop
[NOTE] Package utop is already installed (current version is 2.4.1).
[NOTE] Package core is already installed (current version is v0.12.3).
Here is the sum.ml file from Real World OCaml:
open Core.Std
let rev read_and_accumulate accum =
let line = In_channel.input_line In_channel.stdin in
match line with
| None -> accum
| Some x -> read_and_accumulate (accum +. Float.of_string x)
let () =
printf "Total: %F\n" (read_and_accumulate 0.)
Here's what happens when I try to build it with corebuild:
mymac:Desktop myusr$ corebuild sum.native
+ ocamlfind ocamlc -c -w A-4-33-40-41-42-43-34-44 -strict-sequence -g -bin-annot -short-paths -thread -package core -ppx 'ppx-jane -as-ppx' -o sum.cmo sum.ml
File "sum.ml", line 1, characters 5-13:
1 | open Core.Std
^^^^^^^^
Error: Unbound module Core.Std
Command exited with code 2.
Hint: Recursive traversal of subdirectories was not enabled for this build,
as the working directory does not look like an ocamlbuild project (no
'_tags' or 'myocamlbuild.ml' file). If you have modules in subdirectories,
you should add the option "-r" or create an empty '_tags' file.
To enable recursive traversal for some subdirectories only, you can use the
following '_tags' file:
true: -traverse
<dir1> or <dir2>: traverse
Compilation unsuccessful after building 2 targets (1 cached) in 00:00:00.
Why isn't corebuild linking to the core library? How can I fix this?
The build script loads everything correctly. The module that you're trying to load no longer exists. You're trying to use an old version of the Real World OCaml book together with a very new version of OCaml and Core. The Janestreet Core library has changed a lot since those times. You should either switch to a newer book or downgrade to an older version of OCaml and Core library.
Using modern Core
Since the admission of Dune and module aliases, it is no longer needed to have an extra Std submodule, therefore Janestreet removed it (after a two-year-long deprecation). Therefore, now we're writing
open Core
instead of
open Core.Std (* no longer works *)
The same is true with Core_kernel et alas.
Since OCaml and Janesteet have moved since that time a lot, the newer version of RWO was created with updated examples. It is still a work in progress but looks quite close to be ready. So you can switch to it.
Sticking to older versions of OCaml
If you would like to use the first version of Real World OCaml, then you have to choose a version of OCaml and Janesteet's Core library which are known to be compatible. I failed to find any authoritative recommendations on which version it is better to use with the old book. So I would suggest using OCaml 4.02.3. Then you can install core as usual with opam install core (it should install version 113.33.03), and as far as I remember, it should work with the old book. If you or anyone else is having problems with this version please tell me in the comments section, and I will update this recommendation.
Preface: I am new to OCaml, OPAM, and OASIS.
tldr question: How do I properly set up a package with opam that is not already available in the repository (I can't just do opam install X)? More details follow:
I am trying to include ocaml-glpk in an OCaml project. I installed ocaml-glpk just by running make and make install as stated in the README, and the given example compiles and runs correctly. However, I am using OASIS to generate the build system of my project, and I am not sure how to set it up. I have the same example (renamed to glpkExample.ml in a src folder) and the following in my _oasis file:
Executable "glpkExample"
Path: src
MainIs: glpkExample.ml
CompiledObject: best
BuildDepends:
glpk
After running oasis setup -setup-update dynamic, I run make and get the following error:
ocaml setup.ml -build
Finished, 0 targets (0 cached) in 00:00:00.
+ /home/dimitrios/.opam/system/bin/ocamlfind ocamlopt -g -linkpkg -package glpk src/glpkExample.cmx -o src/glpkExample.native
File "_none_", line 1:
Error: Cannot find file /home/dimitrios/.opam/system/lib/glpk/glpk.cmxa
Command exited with code 2.
Compilation unsuccessful after building 4 targets (3 cached) in 00:00:00.
E: Failure("Command ''/usr/bin/ocamlbuild' src/glpkExample.native -tag debug' terminated with error code 10")
make: *** [build] Error 1
It seems the glpk library is missing a cmxa file needed to compile a native executable. I am not sure how to fix this. To compile glpkExample.ml correctly, my Makefile includes /home/dimitrios/.opam/system/lib/glpk and also uses the OCamlMakefile, which is extremely long and convoluted. Any help on setting this up with OASIS or how to get ocaml-glpk to work nicely with OASIS would be greatly appreciated.
Thanks!
This website is not appropriate for bug reports. You should really report it here.
The temporary solution is to use CompiledObject: byte to compile in bytecode.
If you're using opam then it is best to install application with it, not manually. Try to clean up your system and remove whatever you installed, and then do:
$ eval `opam config env`
$ opam install ocaml-glpk
Afterwards, if glpk is packaged in opam correctly, it should work with your setup, i.e., just with oasis's BuildDepends field and nothing more.
In my project I have a file that uses Core.Std stuff, so I have run
opam install core
and added
open Core.Std
in my file.
When I run
ocamlbuild myprogram.native
it says:
Error: Unbound module Core
pointing to line with the open statement above.
So, I try this:
ocamlbuild -use-ocamlfind -pkgs core.std myprogram.native
and get the following message:
ocamlfind: Package `core.std' not found
So I thought that maybe I needed to run opam install core.std as well, but apparently there is no such thing according to opam. I also tried "open Core.Std;;" in the ocaml repl, but that did not work either. Any ideas?
You can either use corebuild which is usually shipped with this library or, you can try this:
ocamlbuild -use-ocamlfind -pkg core
P.S. use ocamlfind list command to view the list of available packages.
P.P.S. In addition to corebuild they usually ship coretop, a script that allows you to run core-enabled top-level. It uses utop underneath the hood, so make sure that you have installed it with opam install utop (if you're using opam), before your experiments.
Remove .std from your ocamlbuild cmd?