Trouble with Autocomplete

[akcorp2003]

Using:

• 0.6.39 of the plugin
• 1.14.2 of VS Code
• Mac OS Sierra 10.12.6

I'm having trouble with autocomplete. This is what I get:

I'm sure I have merlin installed as I get:

The Merlin toolkit version 2.5.0, for Ocaml 4.04.0

I also included the file associations in my user settings to match *.ml with ocaml. I've also tried reinstalling the plugin but it didn't resolve the issue.

[hackwaly]

Did you setup opam env correctly? What will happen if you execute merlin in the vscode's integrated terminal?

[akcorp2003]

How do I check my opam env? I'm pretty sure it's set up correctly as I can run the opam, ocaml and even utop in my bash terminal. I didn't, however, use brew to install it.

I can run ocamlmerlin -version in the integrated terminal and I get the correct version output as noted in my first comment.

[hackwaly]

Are you sure only autocomplete not works? Does hover tips (show types when hover on variable) and other merlin related features works well?

[akcorp2003]

All the other features don't work either.

I just tried opam remove merlin and opam install merlin but it didn't fix anything.

[hackwaly]

Do you know typescript? You'd better debug ocaml extension to figure out what's happan.

[akcorp2003]

Unfortunately, I don't know Typescript. But how would I get started with debugging an extension? I've never tried to before.

[hackwaly]

See this issue: https://github.com/hackwaly/vscode-ocaml/issues/1#issuecomment-224950931 And this https://code.visualstudio.com/docs/extensions/debugging-extensions

[akcorp2003]

I opened the debug window and got this:

And then I opened the debugger but got no output from the console even if I started typing inside.

'/Applications/Visual Studio Code.app/Contents/MacOS/Electron' --debugBrkPluginHost=46109 --extensionDevelopmentPath=/Users/akuang/OCamlPlugin/vscode-ocaml 

[hackwaly]

The new debug window appears after you press F5 is a new vscode instance with the extension under debugging. You then open your test project folder under that window to check things. The warning is unimportant you can simply ignored.

[akcorp2003]

Where are some suggested breakpoints? I tried hovering over some variables but I get no output in the debug console in the main window (not the new instance). Also, the branch mentioned in the referenced issue doesn't exist.

[hackwaly]

You can define a env variable DEBUG_VSCODE_OCAML=1 to make it log things. Or set breakpoint at src/log.ts:2.

[akcorp2003]

Sorry, I don't know much about TypeScript. How do I define this env variable? Even if I set the breakpoint at src/log.ts:2, it will never enter it if I don't have that variable defined.

[akcorp2003]

Never mind. I got it to output some variables. Will update shortly.

[akcorp2003]

Here is the output after I entered a new line.

command to merlin: ["protocol","version",2]
response from merlin: ["return",{"selected":2,"latest":3,"merlin":"The Merlin toolkit version 2.5.0, for Ocaml 4.04.0"}]
command to merlin: ["checkout","auto","/Users/akuang/OCamlDev/src/filereader.ml"]
response from merlin: ["return",true]
command to merlin: ["tell","start","end","open Printf\n\nlet file = \"/Users/akuang/mf/src/\";;\n\nlet readFirstLine file_name =\n    \n    let line = open_in (file ^ file_name) in\n    try\n        let line_in_file = input_line line in\n            print_endline line_in_file;\n            flush stdout;\n            close_in line\n    with e ->\n        close_in_noerr line;\n        raise e\n\n;;\n\n\n\n\nlet () =\n    readFirstLine \"classes/AccountHierarchyHelper.cls\";;"]

Here is the output after I typed in let.

command to merlin: ["protocol","version",2]
response from merlin: ["return",{"selected":2,"latest":3,"merlin":"The Merlin toolkit version 2.5.0, for Ocaml 4.04.0"}]
command to merlin: ["checkout","auto","/Users/akuang/OCamlDev/src/filereader.ml"]
response from merlin: ["return",true]
command to merlin: ["tell","start","end","open Printf\n\nlet file = \"/Users/akuang/mf/src/\";;\n\nlet readFirstLine file_name =\n    \n    let line = open_in (file ^ file_name) in\n    try\n        let line_in_file = input_line line in\n            print_endline line_in_file;\n            flush stdout;\n            close_in line\n    with e ->\n        close_in_noerr line;\n        raise e\n\n;;\n\nl\n\nlet () =\n    readFirstLine \"classes/AccountHierarchyHelper.cls\";;"]
response from merlin: ["return",true]
command to merlin: ["complete","prefix","l","at",{"line":19,"col":1},"with","doc"]
response from merlin: ["error",{"type":"type","sub":[],"valid":true,"message":"Error: /usr/local/lib/ocaml/pervasives.cmi\nis not a compiled interface for this version of OCaml.\nIt seems to be for a newer version of OCaml."}]
command to merlin: ["checkout","auto","/Users/akuang/OCamlDev/src/filereader.ml"]
response from merlin: ["return",true]
command to merlin: ["tell","start","end","open Printf\n\nlet file = \"/Users/akuang/mf/src/\";;\n\nlet readFirstLine file_name =\n    \n    let line = open_in (file ^ file_name) in\n    try\n        let line_in_file = input_line line in\n            print_endline line_in_file;\n            flush stdout;\n            close_in line\n    with e ->\n        close_in_noerr line;\n        raise e\n\n;;\n\nlet\n\nlet () =\n    readFirstLine \"classes/AccountHierarchyHelper.cls\";;"]
response from merlin: ["return",true]
command to merlin: ["errors"]
response from merlin: ["error",{"type":"type","sub":[],"valid":true,"message":"Error: /usr/local/lib/ocaml/pervasives.cmi\nis not a compiled interface for this version of OCaml.\nIt seems to be for a newer version of OCaml."}]

[hackwaly]

It seems your compiler used by project is not identical with your compiler in env. Do you use opam switch? You can add a option ocaml.useOpamToResolve: true to your workspace .settings.json file then try (You must install merlin under that switch).

[akcorp2003]

I don't think I'm using it as my current version of ocaml is close to the latest:

The OCaml toplevel, version 4.04.0

Even if I set ocaml.useOpamToResolve: true, still no auto-complete.

[hackwaly]

See https://github.com/ocaml/merlin/issues/604. But your problem seems is not that case.

[hackwaly]

I can't help you any more. Open an issue at merlin project if necessary.

[akcorp2003]

Alright. Thanks for giving some pointers though!