From eb2d3bb54a634ef181fc66201352ef72dbf0f6f6 Mon Sep 17 00:00:00 2001
From: Martchus <martchus@gmx.net>
Date: Sat, 19 Nov 2016 14:32:37 +0100
Subject: [PATCH] Check in hasField() whether field is empty

---
 fieldbasedtag.h | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fieldbasedtag.h b/fieldbasedtag.h
index 1e9baea..8c1b814 100644
--- a/fieldbasedtag.h
+++ b/fieldbasedtag.h
@@ -187,7 +187,12 @@ inline bool FieldMapBasedTag<FieldType, Compare>::hasField(KnownField field) con
 template <class FieldType, class Compare>
 inline bool FieldMapBasedTag<FieldType, Compare>::hasField(const typename FieldType::identifierType &id) const
 {
-    return m_fields.count(id);
+    for (auto range = m_fields.equal_range(id); range.first != range.second; ++range.first) {
+        if(!range.first->second.value().isEmpty()) {
+            return true;
+        }
+    }
+    return false;
 }
 
 template <class FieldType, class Compare>