When there are more matches than the single-char label pool (>|L|,
i.e. > 26 with the default), issue two-char labels so matches past
the single-char ceiling are still reachable.
Tactics:
- Cap: 2 * |L| = 52 labels total in two-char mode. The full |L|^2 =
676 space produces visually unusable density on packed buffers;
52 is plenty once the cursor-proximity sort lands them near the
cursor.
- Label order: first char varies slow (26 labels starting with 'f',
next 26 starting with 'j') so only 'f' and 'j' become prefixes.
The remaining 24 letters stay usable for pattern extension in
two-char mode.
- Per-line readability spacing: a 2-char label requires one column
of original text between itself and the previous 2-char label on
the same line. Prevents visual bleed when matches are adjacent
(e.g. '0' search on timestamp-heavy text). Single-char mode
unchanged.
- No global mode flag: a 'prefixes' set, populated while assigning
labels, tells the input loop when to buffer a second keystroke.
The set resets each iteration with 'active'.
swaits
d9788571ec