addr takes line:col, as Look's file:12:5 does

A script that knows a line and column had to count bytes to write #n. `12:5` is now the point at line 12, column 5 (bytes from 1, clamped to the line's end and snapped to a character's start, as Look's cursor is), and it composes like any simple address. A pardes extension, documented as one; sam reads it as a syntax error.

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

2 files changed, 27 insertions, 2 deletions

diff --git a/src/fs-help.txt b/src/fs-help.txt
index 214986a1..324b992e 100644
--- a/src/fs-help.txt
+++ b/src/fs-help.txt
@@ -35,7 +35,7 @@ Below, $m is the mount: $NINE_MOUNT/pardes/<pid, or NAME of --detach=NAME>; PARD
 
 Pitfalls, one each:
   Each open of pane/new makes another pane (ls, stat, find never do); rmdir closes even a dirty one.
-  addr: #n,#m or /regexp/ from the current address (^ $ per line); > never resets it, 0 does; a miss refuses data.
+  addr: #n,#m, 12:5 or /re/ from the current address (^ $ per line); > never resets it, 0 does; a miss refuses data.
   data: > replaces the addr range, : > deletes it, a 2nd > inserts (addr moved); body: > empties all.
   tag reads the path, then its own text; > replaces that text (default words too), >> appends.
   A terminal's body is a history snapshot frozen per open; pty/data is the live stream.
diff --git a/src/ninep/addr.zig b/src/ninep/addr.zig
index ccb08924..f57c62bd 100644
--- a/src/ninep/addr.zig
+++ b/src/ninep/addr.zig
@@ -91,6 +91,26 @@ pub const Addr = struct {
                         if (d < '0' or d > '9') break;
                         n = @min(n * 10 + (d - '0'), std.math.maxInt(u32));
                     }
+                    // pardes's `line:col`, Look's `file:12:5` spelling (look.zig
+                    // parsePathLine): the point at that column of that line, the
+                    // column in bytes from 1, clamped to the line's end and snapped
+                    // to a character's start as Look's cursor is. Not sam's.
+                    if (size == .line and dir == 0 and a.i + 1 < a.expr.len and a.expr[a.i] == ':' and
+                        a.expr[a.i + 1] >= '0' and a.expr[a.i + 1] <= '9')
+                    {
+                        a.i += 1;
+                        var col: u64 = 0;
+                        while (a.i < a.expr.len and a.expr[a.i] >= '0' and a.expr[a.i] <= '9') : (a.i += 1)
+                            col = @min(col * 10 + (a.expr[a.i] - '0'), std.math.maxInt(u32));
+                        const lines = modal.cursorLineCount(a.text);
+                        if (n == 0 or n > lines or col == 0) {
+                            a.err = e_range;
+                            return null;
+                        }
+                        const q = clip(modal.offsetAt(a.text, .{ .row = @intCast(n - 1), .col = @intCast(col - 1) }));
+                        r = .{ .q0 = q, .q1 = q };
+                        continue;
+                    }
                     r = a.number(r, @intCast(n), dir, size) orelse return null;
                     dir = 0;
                     size = .line;
@@ -393,6 +413,11 @@ test "the address language, form by form" {
         .{ .expr = "/two/", .q0 = 4, .q1 = 7 },
         .{ .expr = "/t.o/", .q0 = 4, .q1 = 7 },
         .{ .expr = "1\n", .q0 = 0, .q1 = 4 },
+        // pardes's line:col, composing like any simple address.
+        .{ .expr = "2:2", .q0 = 5, .q1 = 5 },
+        .{ .expr = "2:99", .q0 = 7, .q1 = 7 },
+        .{ .expr = "2:2,3:1", .q0 = 5, .q1 = 8 },
+        .{ .expr = "2:2+#3", .q0 = 8, .q1 = 8 },
     }) |c| {
         _ = th.wr(p, addr, "#0");
         const w = th.wr(p, addr, c.expr);
@@ -441,7 +466,7 @@ test "the address language, form by form" {
     for ([_][2][]const u8{
         .{ "zzz", e_syntax },         .{ "/nomatch/", e_no_match }, .{ "99", e_range },
         .{ "#999", e_range },         .{ "/a[/", e_regexp },        .{ "/(a/", e_regexp },
-        .{ "/*a/", e_regexp },
+        .{ "/*a/", e_regexp },        .{ "99:1", e_range },         .{ "2:0", e_range },
     }) |c| {
         _ = th.wr(p, addr, "#0");
         try testing.expectEqualStrings(c[1], th.wr(p, addr, c[0]).reply.ename);