diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/fs.md | 12 | ||||
| -rw-r--r-- | docs/helix-keys.md | 5 |
2 files changed, 14 insertions, 3 deletions
@@ -280,13 +280,21 @@ the alternatives at that place mvzr takes the first that matches where sam takes the longest (`/gam|gamma/` finds `gam`); in a search begun in the middle of a line, `^` inside an alternation can match there; and in a pattern that spans lines, `^`, `$` and `[^...]` keep mvzr's own meaning. +mvzr backtracks without bound (`a*a*a*a*x` over a hundred `a`s takes a +second), and a search holds the editor, so a pattern with more than four +repeats (`*`, `+`, `{m,n}`) is refused as `regular expression has more than +four repeats`, a long line is searched in overlapping windows (64 KB for +a pattern with at most one repeat, 256, 96 and 40 bytes for two, three and +four), where a match longer than half a window can be missed, and a +search still running after 300 ms fails with `regular expression search +took too long`. pardes has no regex engine of its own on purpose; these are its limits. Normal mode's `s` and `S` search a selection the same way (src/regexp.zig is the one place both call), so `^` there also means a line's start. An address that does not evaluate fails the write with why: `bad address -syntax`, `no match for regexp`, `address out of range` or `bad regular -expression`. A failed write to `addr` leaves no address at all, where acme +syntax`, `no match for regexp`, `address out of range`, `bad regular +expression` or one of the two costs above. A failed write to `addr` leaves no address at all, where acme keeps the old one: until an address is written or `addr` is truncated, reading `addr`, and reading, writing or truncating `data` and `xdata`, fail with `no address: the last one written to addr failed`, so a script that diff --git a/docs/helix-keys.md b/docs/helix-keys.md index f2855b3a..087b83d0 100644 --- a/docs/helix-keys.md +++ b/docs/helix-keys.md @@ -249,7 +249,10 @@ compiles a runtime pattern with no allocator, called the way sam searches (`src/regexp.zig`, shared with a pane's `addr` file): each line is its own haystack, so `^` and `$` match at every line's start and end and `.` never crosses a newline, and a pattern naming `\n` runs over the whole selection. -Where helix's `^` is only the selection's start, this is sam's. +Where helix's `^` is only the selection's start, this is sam's. mvzr +backtracks without bound, so the caps docs/fs.md gives for `addr` hold +here too: more than four repeats will not compile (the selection is left +alone) and a search past 300 ms keeps the matches it found so far. | Key | Behavior | Notes | Status | | --- | --- | --- | --- | |