add operators == (attribute_value, std::string)

src/config.cpp

@@ -31,6 +31,7 @@
 #include <deque>
 #include <istream>
 
+#include <boost/bind.hpp>
 #include <boost/foreach.hpp>
 #include <boost/variant/apply_visitor.hpp>
 #include <boost/variant/get.hpp>
@@ -390,6 +391,16 @@ bool config::attribute_value::operator==(const config::attribute_value &other) c
 	return boost::apply_visitor(equality_visitor(), value_, other.value_);
 }
 
+/**
+ * Checks for equality of the attribute values when viewed as strings.
+ * Exception: Boolean synonyms can be equal ("yes" == "true").
+ * Note: Blanks have no string representation, so do not equal "" (an empty string).
+ */
+bool config::attribute_value::equals(const std::string &str) const
+{
+	return boost::apply_visitor(boost::bind( equality_visitor(), _1, boost::cref(str) ), value_);
+}
+
 std::ostream &operator<<(std::ostream &os, const config::attribute_value &v)
 {
 	// Simple implementation, but defined out-of-line because of the templating

src/config.hpp

@@ -280,6 +280,16 @@ public:
 		bool operator==(const attribute_value &other) const;
 		bool operator!=(const attribute_value &other) const
 		{ return !operator==(other); }
+		// We don't want strange conversions to t_string when doing like (c["a"] == "b")
+		bool equals(const std::string& str) const;
+		friend bool operator==(const attribute_value &val, const std::string &str)
+		{ return val.equals(str); }
+		friend bool operator==(const std::string &str, const attribute_value &val)
+		{ return val.equals(str); }
+		friend bool operator==(const attribute_value &val, const char* str)
+		{ return val.equals(std::string(str)); }
+		friend bool operator==(const char* str, const attribute_value &val)
+		{ return val.equals(std::string(str)); }
 
 		// Streaming:
 		friend std::ostream& operator<<(std::ostream &os, const attribute_value &v);