How to avoid these kind of errors? My understanding is that JETLS is not starting from my current environment. How to make it happen? Or do should I add DataFrames to the main julia environment?

More context helps others understand your problem. Please see below. [image] Please read: make it easier to help you Meta Discussion Welcome to the Julia Discourse! We are enthusiastic about helping Julia programmers, both beginner and experienced. This public…

I use eglot in emacs with JETLS. My main julia environment does not have DataFrames. I make separate packages for each project and install DataFrames separately in each project. My config details below. For JETLS install, I’m using the documentation . ▶ Emacs init and Julia pkg details

Thanks for this. I think I understand the issue, I have to add using DataFrames in the top. JETLS does not understand that the file is part of a package that uses DataFrames. I guess this is how it works?

I’m still confused as to how to edit a package where .jl files use structs and functions declared outside Base.

[image] mahmah: JETLS does not understand that the file is part of a package that uses DataFrames. I guess this is how it works? Well, I work with packages and have nearly nothing in the global environment, and JETLS finds the packages of Project.toml in the project root folder just fine. It …

Thanks! About the last three commands, do they need to be added to the file I’m editing in JETLS or to the current environment?

[image] mahmah: About the last three commands, do they need to be added to the file I’m editing in JETLS or to the current environment? No. Just instantiate the project once in the REPL. But thats what you have to do anyways if you work with projects, if you use JETLS or not. If you want to l…

Question: Even if your jl files are under the src/ folder, but the packages are in the main folder of the project, you don’t have any issue with using?

[image] mahmah: you don’t have any issue with using No, I don’t. Project.toml has to be in the root folder. JETLS needs to know where the root folder is, but as long as I use VSCode it knows that automatically. JETLS normally determines the workspace/project root from the editor’s LSP initia…

Thanks. That question was for @George9000 .

JETLS: `DataFrame` is not defined

New to Julia

George9000 October 12, 2026, 2:12pm 2

More context helps others understand your problem. Please see below.

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You should try jetls, it is awesome! Tooling emacs , jetls	32	3325	March 28, 2026
Hints for using the new JETLS.jl language server General Usage package , jetls	24	1808	March 16, 2026
Looking for Emacs users to help me debug an issue with Emacs, eglot, and jetls Tooling question , emacs , jetls	8	558	May 7, 2026
Emacs-based workflow Tooling emacs	97	16809	December 5, 2022
ERROR: The following package names could not be resolved: * Dataframes General Usage question , package , dataframes	2	904	November 3, 2023

JETLS: `DataFrame` is not defined

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