Use completion

Put the cursor in a name and run M-x completion-at-point, or press M-TAB when the terminal delivers it. This requests suggestions immediately. With the default settings, eligible typing also requests them after 150 ms and at least two Unicode characters. Language separators can admit a request earlier.

Use Up/Down or C-p/C-n to choose, Tab/Return to insert, and Escape/C-g to cancel. Native acceptance replaces the complete name around point as one undo operation. Colored indicators identify functions, fields/properties, types and other candidate kinds. The type label is separate from the inserted name and may be hidden in a narrow pane. No additional font package is required. An enabled language server can supply a checked primary replacement range in the same popup; empty or unavailable semantic results use native fallback. If the selected server item needs resolution, acceptance waits asynchronously. Same-document imports and the primary replacement apply together in one undo. Keep editing or cancel to retire the pending acceptance without a partial edit. Cancellation, selection and a refused edit leave the text and history unchanged. Outside a visible list, these keys retain their normal editing actions.

Change automatic requests

Run M-x completion-auto-mode to toggle automatic requests for this session while keeping manual invocation. Run M-x completion-mode to toggle completion entirely. Neither command writes your configuration.

For a persistent choice, change automatic in the existing [completion] table in ~/.config/rev/config.toml and restart rev. When XDG_CONFIG_HOME is set, use rev/config.toml beneath that directory. For example:

[completion]
automatic = false

Keep the other settings in that table; do not append a duplicate table. Change delay_ms to adjust how long typing waits before requesting suggestions. The complete sample includes timing, contexts and popup keys; the configuration catalog gives allowed ranges.

Find the expected context

Use declarations in Rust, C, Go, JavaScript or TypeScript/TSX, tag/attribute names in HTML, selectors/properties in CSS, or keys/tables in JSON/TOML. Native Org offers task states, tags, property keys, directives, link types and heading targets in their structural positions. Ordinary prose and JSON/TOML values do not produce names. Comments and ordinary strings stay quiet automatically by default. Bracketed paste does not request completion per character.

If no list appears, check the language status, context and session toggles. An immediate manual request can report omitted observations when source or symbol limits apply. Suggestions use current and bounded same-language open buffers; opening a project directory does not index it. No match leaves editing available. See Native completion for exact contexts, ranking, fallback and limits, or Register grammar assets for another explicitly configured language.

To enable semantic results from an installed server, follow Use a language server. It explains unsaved completion, buffer exceptions and explicit recovery while preserving native fallback.

For a guided first insertion, follow Complete Names.