Search forwards
When searching forwards for a match, we start searching at the given position,
in the current row. We use the std.mem.indexOf function, that finds the
relative position of a slice in another slice, or returns null if the slice
isn't contained in the other slice.
Following steps are followed unless a match is returned.
| • | search a slice of the current row [col..] |
| • | reset search column to 0 |
| • | search the following lines |
| • | end of file, no wrapscan? return null |
| • | restart from the beginning of the file |
| • | if you reach the initial line, only search [..col] |
If a match is found, pos.lnr is updated, because the callback will need the
line where it was found.
Editor.zig
/// Start a search forwards.
fn findForward(e: *Editor, query: []const u8, pos: *t.Pos) ?[]const u8 {
var col = pos.col;
var i = pos.lnr;
while (i < e.buffer.rows.items.len) : (i += 1) {
const rowchars = e.rowAt(i).chars.items;
if (indexOf(u8, rowchars[col..], query)) |m| {
pos.lnr = i;
return rowchars[(col + m)..(col + m + query.len)];
}
col = 0; // reset search column
}
if (!opt.wrapscan) {
return null;
}
// wrapscan enabled, search from start of the file to current row
i = 0;
while (i <= pos.lnr) : (i += 1) {
const rowchars = e.rowAt(i).chars.items;
if (indexOf(u8, rowchars, query)) |m| {
pos.lnr = i;
return rowchars[m .. m + query.len];
}
}
return null;
}