diff --git a/src/command.cpp b/src/command.cpp
--- a/src/command.cpp
+++ b/src/command.cpp
@@ -411,7 +411,7 @@ CommandCost DoCommand(TileIndex tile, ui
 		SetTownRatingTestMode(true);
 		res = proc(tile, flags & ~DC_EXEC, p1, p2, text);
 		SetTownRatingTestMode(false);
-		if (CmdFailed(res)) {
+		if (res.Failed()) {
 			goto error;
 		}
 
@@ -431,7 +431,7 @@ CommandCost DoCommand(TileIndex tile, ui
 	/* Execute the command here. All cost-relevant functions set the expenses type
 	 * themselves to the cost object at some point */
 	res = proc(tile, flags, p1, p2, text);
-	if (CmdFailed(res)) {
+	if (res.Failed()) {
 error:
 		res.SetGlobalErrorMessage();
 		_docommand_recursive--;
@@ -507,7 +507,7 @@ bool DoCommandP(TileIndex tile, uint32 p
 	int y = TileY(tile) * TILE_SIZE;
 
 	CommandCost res = DoCommandPInternal(tile, p1, p2, cmd, callback, text, my_cmd, estimate_only);
-	if (CmdFailed(res)) {
+	if (res.Failed()) {
 		res.SetGlobalErrorMessage();
 
 		/* Only show the error when it's for us. */
@@ -530,7 +530,7 @@ bool DoCommandP(TileIndex tile, uint32 p
 		callback(res, tile, p1, p2);
 	}
 
-	return CmdSucceeded(res);
+	return res.Succeeded();
 }
 
 
@@ -621,7 +621,7 @@ CommandCost DoCommandPInternal(TileIndex
 		 * (unless it's a command where the test and
 		 * execution phase might return different costs)
 		 * we bail out here. */
-		if (CmdFailed(res) || estimate_only ||
+		if (res.Failed() || estimate_only ||
 				(!test_and_exec_can_differ && !CheckCompanyHasMoney(res))) {
 			return_dcpi(res, false);
 		}
@@ -656,8 +656,8 @@ CommandCost DoCommandPInternal(TileIndex
 	 * check whether the test and execution have yielded the same
 	 * result, i.e. cost and error state are the same. */
 	if (!test_and_exec_can_differ && !skip_test) {
-		assert(res.GetCost() == res2.GetCost() && CmdFailed(res) == CmdFailed(res2)); // sanity check
-	} else if (CmdFailed(res2)) {
+		assert(res.GetCost() == res2.GetCost() && res.Failed() == res2.Failed()); // sanity check
+	} else if (res2.Failed()) {
 		return_dcpi(res2, false);
 	}