diff --git a/eek/eek-symbol.c b/eek/eek-symbol.c
index d19c80ac..9cfbeb12 100644
--- a/eek/eek-symbol.c
+++ b/eek/eek-symbol.c
@@ -301,3 +301,17 @@ eek_symbol_get_modifier_mask (EekSymbol *symbol)
     priv = EEK_SYMBOL_GET_PRIVATE(symbol);
     return priv->modifier_mask;
 }
+
+/**
+ * eek_symbol_is_modifier:
+ * @symbol: an #EekSymbol
+ *
+ * Check if @symbol is a modifier.
+ * Returns: %TRUE if @symbol is a modifier.
+ */
+gboolean
+eek_symbol_is_modifier (EekSymbol *symbol)
+{
+    return eek_symbol_get_modifier_mask (symbol) != 0;
+}
+
diff --git a/eek/eek-symbol.h b/eek/eek-symbol.h
index 6342a0bc..f7af9cff 100644
--- a/eek/eek-symbol.h
+++ b/eek/eek-symbol.h
@@ -86,16 +86,7 @@ EekSymbolCategory     eek_symbol_get_category      (EekSymbol        *symbol);
 EekModifierType       eek_symbol_get_modifier_mask (EekSymbol        *keysym);
 void                  eek_symbol_set_modifier_mask (EekSymbol        *keysym,
                                                     EekModifierType   mask);
-
-/**
- * eek_symbol_is_modifier:
- * @symbol: an #EekSymbol
- *
- * Check if @symbol is a modifier.
- * Returns: %TRUE if @symbol is a modifier.
- */
-#define eek_symbol_is_modifier(symbol) \
-    (eek_symbol_get_modifier_mask ((symbol)) != 0)
+gboolean              eek_symbol_is_modifier       (EekSymbol        *symbol);
 
 G_END_DECLS