Includes improvement

* `set_line` function now returns an int rather than a bool. Values are 0 for success, 1 for invalid line and 2 for invalid coloumn, as well as -1 for an internal error.
* You can no longer go beyond the maximum coloumn in form input. For example if the input has 50 characters in length, you can go up to 51, because 51 will be the blank character from which you can continue to write from the end. This change closes samtupy#62.
* Improved the touch.nvgt `is_available` method's return value as `return dev.length() > 0;` for short.

release/include/form.nvgt

@@ -1727,19 +1727,19 @@ class audio_form {
 		}
 		return c_form[control_index].get_line_column();
 	}
-	bool set_line(int control_index, int line, int col = 1, bool speak_result = false) {
+	int set_line(int control_index, int line, int col = 1, bool speak_result = true) {
 		form_error = 0;
 		if (!active) {
 			form_error = form_error_no_window;
-			return false;
+			return -1;
 		}
 		if ((control_index < 0) || (control_index > c_form.length() - 1)) {
 			form_error = form_error_invalid_index;
-			return false;
+			return -1;
 		}
 		if (c_form[control_index].type != ct_input || !c_form[control_index].active) {
 			form_error = form_error_invalid_control;
-			return false;
+			return -1;
 		}
 		return c_form[control_index].set_line(line, col, !speak_result);
 	}
@@ -2923,10 +2923,10 @@ class control {
 		}
 		return col;
 	}
-	bool set_line(int line, int col = 1, bool silent = false) {
-		if (type != ct_input) return false;
+	int set_line(int line, int col = 1, bool silent = false) {
+		if (type != ct_input) return -1;
 		if (col < 1) col = 1;
-		int max_col = col;
+		int max_col = text.length() + 1;
 		int pos = 0;
 		if (line > 1)
 			pos = bgt_string_contains(text, "\n", line - 1);
@@ -2935,16 +2935,18 @@ class control {
 			if (pos2 > -1) max_col = pos2 - pos - 1;
 		} else {
 			if (!silent) speak("line number out of range");
-			return false;
+			return 1;
+		}
+		if (col > max_col) {
+			if (!silent) speak("Column out of range");
+			return 2;
 		}
-		if (col > max_col) col = max_col;
 		if (pos==0) col--;
 		pos += col;
 		cursor = pos;
 		sel_start = -1;
 		sel_end = -1;
-		if (!silent) speak(read_line(current_line_start_position()), false);
-		return true;
+		return 0;
 	}
 	bool search(const string& in text, int dir = 1, bool silent = false) {
 		if (type == ct_list) {
@@ -3909,9 +3911,9 @@ class go_to_index : utility_form {
 				f.focus(f_col);
 				return;
 			}
-			if (!parent.set_line(control_index, parse_int(idx), parse_int(col))) {
-				speak("invalid line number!");
-				f.focus(f_index);
+			int success = parent.set_line(control_index, parse_int(idx), parse_int(col));
+			if (success!=0) {
+				f.focus((success == 2 ? f_col : f_index));
 			} else {
 				@parent.utility_form = null;
 				parent.focus_interrupt(control_index);

release/include/touch.nvgt

@@ -129,7 +129,7 @@ class touch_gesture_manager {
 	}
 	bool is_available() {
 		uint64[]@ dev = get_touch_devices();
-		return dev.length() < 1 ? false : true;
+		return dev.length() > 0;
 	}
 	bool add_touch_interface(touch_interface@i) {
 		if (@i == null) return false;