K and Alt-K keep or drop the ranges a regex matches in; Alt-: turns every range forward

K and Alt-K share the s/S prompt, which now carries a mode rather than a
split flag: a range stays when a match starts inside it (K) or when none does
(Alt-K), the primary becomes the first, and keeping none leaves the selection
as it was (helix keep_or_remove_matches). Alt-: is ensure_selections_forward.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 12 insertions, 3 deletions

diff --git a/src/modal.zig b/src/modal.zig
index 34c4dac7..f5f3081e 100644
--- a/src/modal.zig
+++ b/src/modal.zig
@@ -97,6 +97,9 @@ pub const Normal = struct {
         trim_sels,
         select_regex,
         split_regex,
+        keep_regex,
+        remove_regex,
+        ensure_forward,
 
         delete,
         delete_noyank,
@@ -210,6 +213,8 @@ pub const Normal = struct {
         }
     };
 
+    /// what the s/S/K/Alt-K prompt does with its pattern's matches
+    pub const RegexMode = enum { select, split, keep, remove };
     pub const Scope = enum { once, per_selection };
     pub const Direction = enum { backward, forward };
     pub const Motion = enum {
@@ -262,6 +267,7 @@ pub const Normal = struct {
         merge,
         merge_consecutive,
         trim,
+        ensure_forward,
     };
     pub const Edit = enum {
         delete,
@@ -314,7 +320,7 @@ pub const Normal = struct {
         insert: struct { kind: Insert, count: u32 },
         select: struct { kind: Select, count: u32 },
         multi: struct { kind: Multi, count: u32 },
-        select_regex: bool, // false = select, true = split
+        select_regex: RegexMode,
         edit: struct { kind: Edit, count: u32 },
         lsp: Lsp,
         adjust_number: i64,
@@ -577,8 +583,11 @@ pub const Normal = struct {
         if (key.has(.merge_sels)) return resultAction(.{ .multi = .{ .kind = .merge, .count = count } });
         if (key.has(.merge_consecutive_sels)) return resultAction(.{ .multi = .{ .kind = .merge_consecutive, .count = count } });
         if (key.has(.trim_sels)) return resultAction(.{ .multi = .{ .kind = .trim, .count = count } });
-        if (key.has(.select_regex)) return resultAction(.{ .select_regex = false });
-        if (key.has(.split_regex)) return resultAction(.{ .select_regex = true });
+        if (key.has(.select_regex)) return resultAction(.{ .select_regex = .select });
+        if (key.has(.split_regex)) return resultAction(.{ .select_regex = .split });
+        if (key.has(.keep_regex)) return resultAction(.{ .select_regex = .keep });
+        if (key.has(.remove_regex)) return resultAction(.{ .select_regex = .remove });
+        if (key.has(.ensure_forward)) return resultAction(.{ .multi = .{ .kind = .ensure_forward, .count = count } });
 
         if (key.has(.delete)) return resultAction(.{ .edit = .{ .kind = .delete, .count = count } });
         if (key.has(.delete_noyank)) return resultAction(.{ .edit = .{ .kind = .delete_noyank, .count = count } });