opa-watch

What is opa-watch

opa-watch provides a project-based 'verify & launch loop' for Opa. This makes developpement with Opa even more fun and more productive.

Each time you do a modification on your project, your project is automatically verified by the Opa compiler (syntax, semantics, client/server distribution ...) and launched. opa-watch is editor-independant so it will work in any environment.

How to use it

Assuming your project is compatible with opa-watch, in a terminal, start opa-watch:

opa-watch --src-dir path/opa_project Or just without argument when launched in the current directory.

You will be notifed of compilation error if any. On the terminal you should have a message:

Change detected: compilation OK, run OK

And you should have in your notification area the following message:

Launched : opa_project

Edit any opa file inside, like the code for your project home page. The previous two message appears again, indicating that the modification has been processed. You can see the result immediatly using your browser. (firefox localhost:2001)

Edit again, when the message Launched appears, you can reload the home page and see the results of your modifications.

If your edit breaks the compilation or the launch, we will be notified. For instance, if you introduce a type error, we will have the following notification:

FAILURE : opa_project

Error: File "src/view/page.opa", line 1, characters 3-7, (1:3-1:7 | 3-7)

Type Conflict

(1:3-1:3) int

(1:5-1:7) float

The types of the first argument and the second argument

of function + of stdlib.core should be the same

You can correct the error and continue to work on your project, at any time the project is correct again, the last version will be launched and testable in your browser.

FAQ

Is my project supported?

It should work off-the-shelf with any project created by opa-create or containing an opa.conf or a Makefile files. It can be easily customized to work with most projects.

Is my Makefile supported?

If make builds your project and make run launches or relaunches your project, then yes it is supported.

My Makefile is not supported, what should I do?

Assuming make target1 is compiling your project, generating target1.exe. You can do: opa-watch --src-dir path/opa_project --command "make target1.exe" --command "killall target1 && target1.exe" See "How to use with project with custom build rules?" for explanations.

How to use for a project with custom build rules?

You can give the list of commands to build and launch your project. Ensure that relaunching is supported by terminating a previously launched version. The last command is assumed to be the launch command and its termination is not waited for. (if not, use --no-launch) For instance: opa-watch --src-dir path/opa_project --command "build_command" --command "killall launch.exe" --comand "launch.exe"

How to use specific opa options without specifying --command?

You can use --opa-opt. For instance if your project is in classic syntax: opa-watch --src-dir path/opa_project --opa-opt "--parser classic"

How to avoid the --src-dir option?

The current directory will be use if --src-dir is omitted.

Are Mac and Windows supported?

opa-watch should work but the notification feature is not working yet.

Can notification appeared in my favorite text editor?

We plan to support notification in emacs and Sublime Text, and to provide a simple way to have it on other editor.

Contributing

opa-watch is released under the MIT license.

Please contribute bug fixes, doc fixes and new features!