Use ranged-for to iterate over value_sett:valuest

This is easier to read and simplifies switching between representations.

Author: tautschnig

src/pointer-analysis/value_set.cpp

@@ -98,14 +98,11 @@ void value_sett::output(
   const namespacet &ns,
   std::ostream &out) const
 {
-  for(valuest::const_iterator
-      v_it=values.begin();
-      v_it!=values.end();
-      v_it++)
+  for(const auto &values_entry : values)
   {
     irep_idt identifier, display_name;
 
-    const entryt &e=v_it->second;
+    const entryt &e = values_entry.second;
 
     if(has_prefix(id2string(e.identifier), "value_set::dynamic_object"))
     {

src/pointer-analysis/value_set_analysis.cpp

@@ -41,14 +41,11 @@ void value_sets_to_xml(
     xmlt &i=dest.new_element("instruction");
     i.new_element()=::xml(location);
 
-    for(value_sett::valuest::const_iterator
-        v_it=value_set.values.begin();
-        v_it!=value_set.values.end();
-        v_it++)
+    for(const auto &values_entry : value_set.values)
     {
       xmlt &var=i.new_element("variable");
       var.new_element("identifier").data=
-        id2string(v_it->first);
+        id2string(values_entry.first);
 
       #if 0
       const value_sett::expr_sett &expr_set=