Crate improv_tui 

improv-tui: a VisiCalc-style pivot grid over an Improv model.

Usage: improv-tui <model.db | postgres://…?model=NAME>

The binary is a thin shell: run owns the real terminal (raw mode, alt screen, panic hook) and feeds crossterm events into event_loop, which is generic over the ratatui backend and the event source so tests can drive it with a TestBackend and a scripted Vec<Event>.

Modules

app 🔒

App state and the pure pivot-grid logic (terminal-free, unit-tested).

complete 🔒

Formula-edit assistance, terminal-free: Tab completion of the identifier before the caret, and the ghost text of the parameters still to type.

diagnose 🔒

Located formula errors, terminal-free: the span of text a [ParseError] is about, its message, and a hint for the common cases (a misspelled name, the wrong number of arguments, an unclosed ().

edit 🔒

The edit line for a cell value or a formula: its text and a caret.

fnhelp 🔒

Function help overlay state (? / F1): a search line over the built-in functions, the ranked results, and the selection in them. Pure state, terminal-free; ui draws it and main feeds it keys.

ui 🔒

Rendering: a status box (title, prompt/message, pages, filters, key help) sized to its content, over the pivot grid as a table.

Functions

event_loop 🔒

Draw, then handle one event, until the app quits or events runs dry.

filter_row_under_cursor 🔒

Toggle the visibility of the row item under the cursor within its (row) category. Repeated ‘f’ on different rows narrows the row axis to a subset.

handle_event 🔒

Dispatch one terminal event by mode (edit / command prompt / normal).

help_key 🔒

Keys while the function help overlay is open: type to search, move the selection, Enter inserts NAME( into an edit in progress, Esc closes.

line_key 🔒

Line-editing keys for the command prompt (the cell edit has a caret: edit::LineEdit::key).

load 🔒

Open the model at path and build the app state.

main 🔒

normal_key 🔒

Key handling in normal (navigation) mode.

restore 🔒

Undo terminal setup. Safe to call multiple times.

revert 🔒

Reload the model from path, dropping this session’s unsaved edits. The way out of a save conflict: the quit autosave refuses to clobber another writer, so revert, pick up their changes, and redo yours. On failure the session is untouched.

run 🔒

Enter the alt screen, run the loop, and always restore the terminal — even on error or panic — then autosave.

save 🔒

Autosave the (possibly edited) model back to path on clean exit; edits are held in memory during the session.

save_current_view 🔒

Save the current layout as a generated “view N” name and persist to path. (Inline text entry is intentionally omitted; the view can be renamed via a future dialog. Documented simplification.)