make doc.meta an unordered_map

src/query/recollq.cpp

@@ -61,8 +61,8 @@ void output_fields(vector<string> fields, Rcl::Doc& doc,
 {
     if (fields.empty()) {
         map<string,string>::const_iterator it;
-        for (it = doc.meta.begin();it != doc.meta.end(); it++) {
-            fields.push_back(it->first);
+        for (const auto& entry : doc.meta) {
+            fields.push_back(entry.first);
         }
     }
     for (vector<string>::const_iterator it = fields.begin();
@@ -406,9 +406,8 @@ endopts:
 		<< doc.fbytes << "\tbytes" << "\t"
 		<<  endl;
 	    if (op_flags & OPT_m) {
-		for (map<string,string>::const_iterator it = doc.meta.begin();
-		     it != doc.meta.end(); it++) {
-		    cout << it->first << " = " << it->second << endl;
+		for (const auto ent : doc.meta) {
+		    cout << ent.first << " = " << ent.second << endl;
 		}
 	    }
             if (op_flags & OPT_A) {

src/query/reslistpager.cpp

@@ -313,10 +313,9 @@ void ResListPager::displayDoc(RclConfig *config, int i, Rcl::Doc& doc,
     subs["x"] = xdocidbuf;
     
     // Let %(xx) access all metadata. HTML-neuter everything:
-    for (map<string,string>::iterator it = doc.meta.begin(); 
-	 it != doc.meta.end(); it++) {
-	if (!it->first.empty()) 
-	    subs[it->first] = maybeEscapeHtml(it->second);
+    for (const auto& entry : doc.meta) {
+	if (!entry.first.empty()) 
+	    subs[entry.first] = maybeEscapeHtml(entry.second);
     }
 
     string formatted;

src/query/sortseq.cpp

@@ -32,9 +32,8 @@ public:
     { 
 	LOGDEB1("Comparing .. \n" );
 
-	map<string,string>::const_iterator xit, yit;
-	xit = x->meta.find(ss.field);
-	yit = y->meta.find(ss.field);
+	const auto xit = x->meta.find(ss.field);
+	const auto yit = y->meta.find(ss.field);
 	if (xit == x->meta.end() || yit == y->meta.end())
 	    return 0;
 	return ss.desc ? yit->second < xit->second : xit->second < yit->second;