sam: introduce `m as an address refering to mark m

3 files changed, 21 insertions, 0 deletions

diff --git a/README.md b/README.md
index ab8d3dc..e07e4ec 100644
--- a/README.md
+++ b/README.md
@@ -358,6 +358,11 @@ Operators can be forced to work line wise by specifying `V`.
 
   Other differences compared to sam include:
 
+  - New addresses:
+
+     * `%` as an alias for `,` or `0,$`
+     * `` `m `` refers to mark `m`
+
   - The following commands are deliberately not implemented:
 
      * move `m`
diff --git a/sam.c b/sam.c
index 7499242..2c4fcb6 100644
--- a/sam.c
+++ b/sam.c
@@ -405,6 +405,7 @@ const char *sam_error(enum SamError err) {
 		[SAM_ERR_COMMAND]         = "Unknown command",
 		[SAM_ERR_EXECUTE]         = "Error executing command",
 		[SAM_ERR_NEWLINE]         = "Newline expected",
+		[SAM_ERR_MARK]            = "Invalid mark",
 	};
 
 	return err < LENGTH(error_msg) ? error_msg[err] : NULL;
@@ -581,6 +582,14 @@ static Address *address_parse_simple(Vis *vis, const char **s, enum SamError *er
 		addr.type = 'l';
 		addr.number = parse_number(s);
 		break;
+	case '`':
+		(*s)++;
+		if ((addr.number = vis_mark_from(vis, **s)) == VIS_MARK_INVALID) {
+			*err = SAM_ERR_MARK;
+			return NULL;
+		}
+		(*s)++;
+		break;
 	case '/': /* regexp forwards */
 	case '?': /* regexp backwards */
 		addr.regex = parse_regex(vis, s);
@@ -882,6 +891,12 @@ static Filerange address_evaluate(Address *addr, File *file, Filerange *range, i
 		case 'g':
 			ret = address_line_evaluate(addr, file, range, sign);
 			break;
+		case '`':
+		{
+			size_t pos = text_mark_get(file->text, file->marks[addr->number]);
+			ret = text_range_new(pos, pos);
+			break;
+		}
 		case '?':
 			sign = sign == 0 ? -1 : -sign;
 			/* fall through */
diff --git a/sam.h b/sam.h
index 7d063f4..717f5a4 100644
--- a/sam.h
+++ b/sam.h
@@ -15,6 +15,7 @@ enum SamError {
 	SAM_ERR_COMMAND,
 	SAM_ERR_EXECUTE,
 	SAM_ERR_NEWLINE,
+	SAM_ERR_MARK,
 };
 
 bool sam_init(Vis*);