# 17 — `_` is global rather than local

**Status:** open

The `_` result variable from interactive commands (`!cmd`) is set as a global via `lua_setglobal(L, "_")`. This has several implications:

- It can escape its scope and pollute other scopes
- A function may silently overwrite `_` if it uses shell commands internally, surprising the caller
- Lua convention uses `_` as a throwaway variable in `for` loops (`for _, v in pairs(t)`)

## Investigation needed

- What are the concrete consequences of `_` being global vs local?
- Can we make it local to the REPL line instead?
- Should we use a different name entirely?