Removing a cell in watch mode prevents redeclaring variables #6594
Description
Describe the bug
When editing a notebook in watch mode, if I delete a cell containing a variable in an external editor while Marimo is in watch mode, Marimo prevents redefining the variable in a new cell:
This cell wasn't run because it has errors
This cell redefines variables from other cells.'my_var' was also defined by:
- cell--1
This (annoyingly) happens if I save the file in the external editor without remembering to hit save in Marimo after defining the variable in a new cell.
Steps to reproduce:
- Open a Marimo notebook in watch mode
- Define a new cell with
x=4, run the cell. - Delete the cell in an external editor and save the file. (Alternatively, if you didn't save the notebook in Marimo, just save the file again)
- Try defining a new cell in Marimo again with
x=3.
This issue is similar, but not a dupe of #1016.
Will you submit a PR?
- Yes
Environment
Details
{
"marimo": "0.16.2",
"editable": false,
"location": "C:/Users/avg170002/Code/biaxial-bioreactor/code/.venv/Lib/site-packages/marimo",
"OS": "Windows",
"OS Version": "11",
"Processor": "Intel64 Family 6 Model 198 Stepping 2, GenuineIntel",
"Python Version": "3.13.6",
"Locale": "en_US",
"Binaries": {
"Browser": "--",
"Node": "v22.18.0"
},
"Dependencies": {
"click": "8.2.1",
"docutils": "0.22",
"itsdangerous": "2.2.0",
"jedi": "0.19.2",
"markdown": "3.8.2",
"narwhals": "2.2.0",
"packaging": "25.0",
"psutil": "7.0.0",
"pygments": "2.19.2",
"pymdown-extensions": "10.16.1",
"pyyaml": "6.0.2",
"starlette": "0.47.3",
"tomlkit": "0.13.3",
"typing-extensions": "4.15.0",
"uvicorn": "0.35.0",
"websockets": "15.0.1"
},
"Optional Dependencies": {
"altair": "5.5.0",
"duckdb": "1.3.2",
"nbformat": "5.10.4",
"openai": "1.102.0",
"pandas": "2.3.2",
"polars": "1.32.3",
"pyarrow": "21.0.0",
"loro": "1.5.4",
"pytest": "8.4.1",
"python-lsp-ruff": "2.2.2",
"python-lsp-server": "1.13.1",
"ruff": "0.12.11",
"sqlglot": "27.9.0"
},
"Experimental Flags": {}
}
Code to reproduce
No response