diff --git a/docs/lang/preprocessor.md b/docs/lang/preprocessor.md
index 1bacdd62..35c211f8 100644
--- a/docs/lang/preprocessor.md
+++ b/docs/lang/preprocessor.md
@@ -114,6 +114,11 @@ Emits a diagnostic message.
 `#warn` emits a warning. It may be treated as an error depending on compilation options.  
 `#info` emits a benign diagnostic message.
 
+### `#infoeval`
+
+    #infoeval <expr>
+    
+Evaluates an expression and emits the result as a diagnostic message.
 
 ### `#use`
 
diff --git a/src/main/scala/millfork/parser/Preprocessor.scala b/src/main/scala/millfork/parser/Preprocessor.scala
index 7b7900de..4d9d16db 100644
--- a/src/main/scala/millfork/parser/Preprocessor.scala
+++ b/src/main/scala/millfork/parser/Preprocessor.scala
@@ -68,6 +68,11 @@ object Preprocessor {
             case "error" => if (enabled) log.error(param, pos)
             case "warn" => if (enabled) log.warn(param, pos)
             case "info" => if (enabled) log.info(param, pos)
+            case "infoeval" =>
+              if (enabled) {
+                val value = evalParam(param, pos)
+                log.info(s"$param = $value", pos)
+              }
             case "if" =>
               if (enabled) {
                 val value = evalParam(param, pos)