emacs-direnv VS estree

env-commander-mode is a simple mode which allows any shell commands that Emacs invokes to run one or more commands beforehand to initialize the shell environment. There are many Emacs packages which can configure process environments, for example, direnv, but they lack the ability to go a step further and define shell functions and aliases, which is often required by "virtual environment" tools. For those who prefer interacting with shell commands via shell-command rather than shell, eshell, or term, env-commander-mode is here to assist.

I'm using nix to manage python dependencies (see excerpt of flake.nix below) but this means those python dependencies are in a /nix directory, so when lsp tries to figure out project root for them, it thinks they have nothing to do with my own project. Also I'm using emacs-direnv to transparently switch into nix environments (.envrc + use flake), so direnv (correctly) unloads my LSP executable (configured in flake.nix), so even if they should be considered totally separate projects LSP-mode doesn't know how to start up the server.

I've had a good experience with direnv[1] and emacs-direnv[2].

Direnv can automatically load an environment when you enter a directory, so it automatically "opens" virtualenvs/nix shells/etc. The Emacs direnv mode ensures that each buffer sees the direnv mode for its project directory.

I've found this to be a great compromise between automatic behavior on the one hand and transparency + control on the other—I get the right environment loaded automatically very consistently and, if something goes wrong, I can open a shell and poke around to see what's going on (is my nix shell messed up? is the right tool not loaded via direnv? etc). The only time I need to do anything manually is if I make a change to the environment and need to update Emacs about it, in which case I just run M-x direnv-update-environment.

Once I got this set up, I can just rely on executable-find to check for (and find) exactly the right tool on a per-project basis—no more worrying about global or seeing the wrong version of a tool. This also made it easy to do stuff like only run formatting if the corresponding tool is available: I add hooks to various programming language modes that only turn on lsp/formatting/etc if executable-find sees the corresponding executable.

Compared to the hassle I've had to go through helping my colleagues debug VSCode not seeing the right conda environment, virtualenv or the right version of various tools, Emacs + direnv has been a far nicer and more consistent experience.

[1]: https://direnv.net/

[2]: https://github.com/wbolster/emacs-direnv

Alternatively from what /u/hantva said, you can try using direnv and its integration with Emacs. This has a benefit of scaling better if you have more than one such project as each set of env vars is separate.

I'm using lorri and emacs-direnv together, works perfectly fine for me.

Thanks, I'll check this out if I can't get my ideal setup to work. Presume you meant this: https://github.com/wbolster/emacs-direnv ?

I first install direnv which allows me to have a different environment per directory, or in my case, a project. And there is a project that connects Emacs to this. https://github.com/wbolster/emacs-direnv

I use this to source .envrc files into my emacs environment: https://github.com/wbolster/emacs-direnv

almost. to integrate with a shell, you would indeed hook it onto the shell's prompt function. to integrate it with Emacs, you would use https://github.com/wbolster/emacs-direnv , so Emacs sees the project specific process environment too. the isolation is primarily achieved by setting up a custom PATH, PYTHON_PATH and similar vars

ESLint's AST format, ESTree, would represent this line of code as:

That was a super interesting link, thank you.

For the ontological problem, I presume you're referring to how there are so many differing ideas of how to represent ASTs (apologies for mixing languages, these URLs were just handy):

* https://lisperator.net/uglifyjs/ast#nodes

* https://github.com/estree/estree#the-estree-spec

* ... likely others

which makes it hard for ls1 to ask ls2 about "the for-of iteration variable Node" because ls2 could be using UglifyJS or ESTree or their own(!) AST nomenclature?

And all of this is made worse by (e.g.) Java1.3 versus Java19 because languages are rarely static

I find it better to actually look at the AST for javascript.

These are expressions:

https://github.com/estree/estree/blob/master/es5.md#expressi...

These are statements:

https://github.com/estree/estree/blob/master/es5.md#statemen...

I guess the confusing part for many is how an expression can also be a statement. But if you look at the ExpressionStatement you see that an expression is not also a statement. It's just the wrapper statement!

When I started the NodeSecure project I had almost no experience 🐤 with AST (Abstract Syntax Tree). My first time was on the SlimIO project to generate codes dynamically with the astring package (and I had also looked at the ESTree specification).

ESTree compatible output, AST explorer on WASM

The parser we wrote transforms the GraphQL AST into ESTree structure, so it allows you to travel the GraphQL AST tree easily.

For espree parser(the one eslint uses) we can refer here Eslint AST Node Types